--- a/b2g/chrome/content/shell.js
+++ b/b2g/chrome/content/shell.js
@@ -59,20 +59,18 @@ if (isGonk) {
     return libcutils;
   });
 }
 
 XPCOMUtils.defineLazyServiceGetter(Services, 'captivePortalDetector',
                                   '@mozilla.org/toolkit/captive-detector;1',
                                   'nsICaptivePortalDetector');
 
-if (AppConstants.MOZ_SAFE_BROWSING) {
-  XPCOMUtils.defineLazyModuleGetter(this, "SafeBrowsing",
-                "resource://gre/modules/SafeBrowsing.jsm");
-}
+XPCOMUtils.defineLazyModuleGetter(this, "SafeBrowsing",
+              "resource://gre/modules/SafeBrowsing.jsm");
 
 XPCOMUtils.defineLazyModuleGetter(this, "SafeMode",
                                   "resource://gre/modules/SafeMode.jsm");
 
 window.performance.measure('gecko-shell-jsm-loaded', 'gecko-shell-loadstart');
 
 function debug(str) {
   dump(' -*- Shell.js: ' + str + '\n');
@@ -429,21 +427,19 @@ var shell = {
     window.performance.mark('gecko-shell-system-frame-set');
 
     ppmm.addMessageListener("content-handler", this);
     ppmm.addMessageListener("dial-handler", this);
     ppmm.addMessageListener("sms-handler", this);
     ppmm.addMessageListener("mail-handler", this);
     ppmm.addMessageListener("file-picker", this);
 
-    if (AppConstants.MOZ_SAFE_BROWSING) {
-      setTimeout(function() {
-        SafeBrowsing.init();
-      }, 5000);
-    }
+    setTimeout(function() {
+      SafeBrowsing.init();
+    }, 5000);
   },
 
   stop: function shell_stop() {
     window.removeEventListener('unload', this);
     window.removeEventListener('keydown', this, true);
     window.removeEventListener('keyup', this, true);
     window.removeEventListener('MozApplicationManifest', this);
     window.removeEventListener('sizemodechange', this);

--- a/b2g/confvars.sh
+++ b/b2g/confvars.sh
@@ -12,18 +12,16 @@ MOZ_UA_OS_AGNOSTIC=1
 
 MOZ_B2G_VERSION=2.6.0.0-prerelease
 MOZ_B2G_OS_NAME=Boot2Gecko
 
 MOZ_BRANDING_DIRECTORY=b2g/branding/unofficial
 MOZ_OFFICIAL_BRANDING_DIRECTORY=b2g/branding/official
 # MOZ_APP_DISPLAYNAME is set by branding/configure.sh
 
-MOZ_SAFE_BROWSING=1
-
 MOZ_NO_SMART_CARDS=1
 MOZ_APP_STATIC_INI=1
 MOZ_NO_EV_CERTS=1
 
 if test "$OS_TARGET" = "Android"; then
 MOZ_CAPTURE=1
 MOZ_RAW=1
 MOZ_AUDIO_CHANNEL_MANAGER=1

--- a/b2g/graphene/confvars.sh
+++ b/b2g/graphene/confvars.sh
@@ -19,17 +19,16 @@ MOZ_APP_UA_NAME=Firefox
 
 MOZ_B2G_VERSION=2.6.0.0-prerelease
 MOZ_B2G_OS_NAME=Boot2Gecko
 
 MOZ_BRANDING_DIRECTORY=b2g/branding/unofficial
 MOZ_OFFICIAL_BRANDING_DIRECTORY=b2g/branding/official
 # MOZ_APP_DISPLAYNAME is set by branding/configure.sh
 
-MOZ_SAFE_BROWSING=1
 MOZ_CAPTIVEDETECT=1
 
 MOZ_NO_SMART_CARDS=1
 MOZ_APP_STATIC_INI=1
 NSS_NO_LIBPKIX=1
 
 if test "$OS_TARGET" = "Android"; then
 MOZ_CAPTURE=1

--- a/browser/base/content/browser-doctype.inc
+++ b/browser/base/content/browser-doctype.inc
@@ -8,18 +8,16 @@
 <!ENTITY % charsetDTD SYSTEM "chrome://global/locale/charsetMenu.dtd" >
 %charsetDTD;
 <!ENTITY % textcontextDTD SYSTEM "chrome://global/locale/textcontext.dtd" >
 %textcontextDTD;
 <!ENTITY % customizeToolbarDTD SYSTEM "chrome://global/locale/customizeToolbar.dtd">
   %customizeToolbarDTD;
 <!ENTITY % placesDTD SYSTEM "chrome://browser/locale/places/places.dtd">
 %placesDTD;
-#ifdef MOZ_SAFE_BROWSING
 <!ENTITY % safebrowsingDTD SYSTEM "chrome://browser/locale/safebrowsing/phishing-afterload-warning-message.dtd">
 %safebrowsingDTD;
-#endif
 <!ENTITY % aboutHomeDTD SYSTEM "chrome://browser/locale/aboutHome.dtd">
 %aboutHomeDTD;
 <!ENTITY % syncBrandDTD SYSTEM "chrome://browser/locale/syncBrand.dtd">
 %syncBrandDTD;
 ]>
 

--- a/browser/base/content/browser-safebrowsing.js
+++ b/browser/base/content/browser-safebrowsing.js
@@ -1,15 +1,12 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-// Note: this file is not shipped (through jar.mn)
-// if MOZ_SAFE_BROWSING is not defined.
-
 var gSafeBrowsing = {
 
   setReportPhishingMenu: function() {
     // In order to detect whether or not we're at the phishing warning
     // page, we have to check the documentURI instead of the currentURI.
     // This is because when the DocShell loads an error page, the
     // currentURI stays at the original target, while the documentURI
     // will point to the internal error page we loaded instead.

--- a/browser/base/content/browser.css
+++ b/browser/base/content/browser.css
@@ -758,17 +758,17 @@ html|*#fullscreen-exit-button {
 
 
 /* notification anchors should only be visible when their associated
    notifications are */
 .notification-anchor-icon {
   -moz-user-focus: normal;
 }
 
-.blocked-permission-icon:not([showing]),
+#blocked-permissions-container > .blocked-permission-icon:not([showing]),
 .notification-anchor-icon:not([showing]) {
   display: none;
 }
 
 #invalid-form-popup > description {
   max-width: 280px;
 }
 

--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -52,20 +52,18 @@ Cu.import("resource://gre/modules/Notifi
   ["UpdateUtils", "resource://gre/modules/UpdateUtils.jsm"],
   ["Weave", "resource://services-sync/main.js"],
   ["fxAccounts", "resource://gre/modules/FxAccounts.jsm"],
   ["gDevTools", "resource://devtools/client/framework/gDevTools.jsm"],
   ["gDevToolsBrowser", "resource://devtools/client/framework/gDevTools.jsm"],
   ["webrtcUI", "resource:///modules/webrtcUI.jsm", ]
 ].forEach(([name, resource]) => XPCOMUtils.defineLazyModuleGetter(this, name, resource));
 
-if (AppConstants.MOZ_SAFE_BROWSING) {
-  XPCOMUtils.defineLazyModuleGetter(this, "SafeBrowsing",
-    "resource://gre/modules/SafeBrowsing.jsm");
-}
+XPCOMUtils.defineLazyModuleGetter(this, "SafeBrowsing",
+  "resource://gre/modules/SafeBrowsing.jsm");
 
 if (AppConstants.MOZ_CRASHREPORTER) {
   XPCOMUtils.defineLazyModuleGetter(this, "PluginCrashReporter",
     "resource:///modules/ContentCrashHandlers.jsm");
 }
 
 // lazy service getters
 [
@@ -1141,20 +1139,18 @@ var gBrowserInit = {
       }
       // Note: loadOneOrMoreURIs *must not* be called if window.arguments.length >= 3.
       // Such callers expect that window.arguments[0] is handled as a single URI.
       else {
         loadOneOrMoreURIs(uriToLoad);
       }
     }
 
-    if (AppConstants.MOZ_SAFE_BROWSING) {
-      // Bug 778855 - Perf regression if we do this here. To be addressed in bug 779008.
-      setTimeout(function() { SafeBrowsing.init(); }, 2000);
-    }
+    // Bug 778855 - Perf regression if we do this here. To be addressed in bug 779008.
+    setTimeout(function() { SafeBrowsing.init(); }, 2000);
 
     Services.obs.addObserver(gIdentityHandler, "perm-changed", false);
     Services.obs.addObserver(gSessionHistoryObserver, "browser:purge-session-history", false);
     Services.obs.addObserver(gXPInstallObserver, "addon-install-disabled", false);
     Services.obs.addObserver(gXPInstallObserver, "addon-install-started", false);
     Services.obs.addObserver(gXPInstallObserver, "addon-install-blocked", false);
     Services.obs.addObserver(gXPInstallObserver, "addon-install-origin-blocked", false);
     Services.obs.addObserver(gXPInstallObserver, "addon-install-failed", false);
@@ -7372,17 +7368,17 @@ var gIdentityHandler = {
   _createPermissionItem: function (aPermission) {
     let container = document.createElement("hbox");
     container.setAttribute("class", "identity-popup-permission-item");
     container.setAttribute("align", "center");
 
     let img = document.createElement("image");
     let classes = "identity-popup-permission-icon " + aPermission.id + "-icon";
     if (aPermission.state == SitePermissions.BLOCK)
-      classes += " blocked";
+      classes += " blocked-permission-icon";
     if (aPermission.inUse)
       classes += " in-use";
     img.setAttribute("class", classes);
 
     let nameLabel = document.createElement("label");
     nameLabel.setAttribute("flex", "1");
     nameLabel.setAttribute("class", "identity-popup-permission-label");
     nameLabel.textContent = SitePermissions.getPermissionLabel(aPermission.id);

--- a/browser/base/content/global-scripts.inc
+++ b/browser/base/content/global-scripts.inc
@@ -18,19 +18,17 @@
 <script type="application/javascript" src="chrome://browser/content/browser-feeds.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-fullScreenAndPointerLock.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-fullZoom.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-gestureSupport.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-media.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-places.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-plugins.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-refreshblocker.js"/>
-#ifdef MOZ_SAFE_BROWSING
 <script type="application/javascript" src="chrome://browser/content/browser-safebrowsing.js"/>
-#endif
 <script type="application/javascript" src="chrome://browser/content/browser-sidebar.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-social.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-syncui.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-tabsintitlebar.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-thumbnails.js"/>
 <script type="application/javascript" src="chrome://browser/content/browser-trackingprotection.js"/>
 
 #ifdef MOZ_DATA_REPORTING

--- a/browser/base/content/nsContextMenu.js
+++ b/browser/base/content/nsContextMenu.js
@@ -690,18 +690,21 @@ nsContextMenu.prototype = {
       if (this.target instanceof Ci.nsIImageLoadingContent &&
           this.target.currentURI) {
         this.onImage = true;
 
         var request =
           this.target.getRequest(Ci.nsIImageLoadingContent.CURRENT_REQUEST);
         if (request && (request.imageStatus & request.STATUS_SIZE_AVAILABLE))
           this.onLoadedImage = true;
-        if (request && (request.imageStatus & request.STATUS_LOAD_COMPLETE))
+        if (request &&
+            (request.imageStatus & request.STATUS_LOAD_COMPLETE) &&
+            !(request.imageStatus & request.STATUS_ERROR)) {
           this.onCompletedImage = true;
+        }
 
         this.mediaURL = this.target.currentURI.spec;
 
         var descURL = this.target.getAttribute("longdesc");
         if (descURL) {
           this.imageDescURL = makeURLAbsolute(ownerDoc.body.baseURI, descURL);
         }
       }

--- a/browser/base/content/utilityOverlay.js
+++ b/browser/base/content/utilityOverlay.js
@@ -737,18 +737,19 @@ function openTourPage()
   let scope = {}
   Components.utils.import("resource:///modules/UITour.jsm", scope);
   openUILinkIn(scope.UITour.url, "tab");
 }
 
 function buildHelpMenu()
 {
   // Enable/disable the "Report Web Forgery" menu item.
-  if (typeof gSafeBrowsing != "undefined" && AppConstants.MOZ_SAFE_BROWSING)
+  if (typeof gSafeBrowsing != "undefined") {
     gSafeBrowsing.setReportPhishingMenu();
+  }
 }
 
 function isElementVisible(aElement)
 {
   if (!aElement)
     return false;
 
   // If aElement or a direct or indirect parent is hidden or collapsed,

--- a/browser/base/jar.mn
+++ b/browser/base/jar.mn
@@ -82,19 +82,17 @@ browser.jar:
         content/browser/browser-fullScreenAndPointerLock.js  (content/browser-fullScreenAndPointerLock.js)
         content/browser/browser-fullZoom.js           (content/browser-fullZoom.js)
         content/browser/browser-fxaccounts.js         (content/browser-fxaccounts.js)
         content/browser/browser-gestureSupport.js     (content/browser-gestureSupport.js)
         content/browser/browser-media.js              (content/browser-media.js)
         content/browser/browser-places.js             (content/browser-places.js)
         content/browser/browser-plugins.js            (content/browser-plugins.js)
         content/browser/browser-refreshblocker.js     (content/browser-refreshblocker.js)
-#ifdef MOZ_SAFE_BROWSING
         content/browser/browser-safebrowsing.js       (content/browser-safebrowsing.js)
-#endif
         content/browser/browser-sidebar.js            (content/browser-sidebar.js)
         content/browser/browser-social.js             (content/browser-social.js)
         content/browser/browser-syncui.js             (content/browser-syncui.js)
 *       content/browser/browser-tabPreviews.xml       (content/browser-tabPreviews.xml)
 #ifdef CAN_DRAW_IN_TITLEBAR
         content/browser/browser-tabsintitlebar.js       (content/browser-tabsintitlebar.js)
 #else
         content/browser/browser-tabsintitlebar.js       (content/browser-tabsintitlebar-stub.js)
@@ -186,15 +184,13 @@ browser.jar:
         content/browser/webrtcIndicator.js            (content/webrtcIndicator.js)
 #endif
 #ifdef XP_WIN
         content/browser/win6BrowserOverlay.xul        (content/win6BrowserOverlay.xul)
 #endif
 # the following files are browser-specific overrides
 *       content/browser/license.html                  (/toolkit/content/license.html)
 % override chrome://global/content/license.html chrome://browser/content/license.html
-#ifdef MOZ_SAFE_BROWSING
         content/browser/report-phishing-overlay.xul     (content/report-phishing-overlay.xul)
         content/browser/blockedSite.xhtml               (content/blockedSite.xhtml)
 % overlay chrome://browser/content/browser.xul chrome://browser/content/report-phishing-overlay.xul
-#endif
 
 % override chrome://global/content/netError.xhtml chrome://browser/content/aboutNetError.xhtml

--- a/browser/components/about/AboutRedirector.cpp
+++ b/browser/components/about/AboutRedirector.cpp
@@ -30,23 +30,21 @@ struct RedirEntry {
   Entries which do not have URI_SAFE_FOR_UNTRUSTED_CONTENT will run with chrome
   privileges. This is potentially dangerous. Please use
   URI_SAFE_FOR_UNTRUSTED_CONTENT in the third argument to each map item below
   unless your about: page really needs chrome privileges. Security review is
   required before adding new map entries without
   URI_SAFE_FOR_UNTRUSTED_CONTENT.
 */
 static RedirEntry kRedirMap[] = {
-#ifdef MOZ_SAFE_BROWSING
   { "blocked", "chrome://browser/content/blockedSite.xhtml",
     nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |
     nsIAboutModule::URI_CAN_LOAD_IN_CHILD |
     nsIAboutModule::ALLOW_SCRIPT |
     nsIAboutModule::HIDE_FROM_ABOUTABOUT },
-#endif
   { "certerror", "chrome://browser/content/aboutNetError.xhtml",
     nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |
     nsIAboutModule::URI_CAN_LOAD_IN_CHILD |
     nsIAboutModule::ALLOW_SCRIPT |
     nsIAboutModule::HIDE_FROM_ABOUTABOUT },
   { "socialerror", "chrome://browser/content/aboutSocialError.xhtml",
     nsIAboutModule::ALLOW_SCRIPT |
     nsIAboutModule::HIDE_FROM_ABOUTABOUT },

--- a/browser/components/build/nsModule.cpp
+++ b/browser/components/build/nsModule.cpp
@@ -80,19 +80,17 @@ static const mozilla::Module::CIDEntry k
 static const mozilla::Module::ContractIDEntry kBrowserContracts[] = {
     { NS_BROWSERDIRECTORYPROVIDER_CONTRACTID, &kNS_BROWSERDIRECTORYPROVIDER_CID },
 #if defined(XP_WIN)
     { NS_SHELLSERVICE_CONTRACTID, &kNS_SHELLSERVICE_CID },
 #elif defined(MOZ_WIDGET_GTK)
     { NS_SHELLSERVICE_CONTRACTID, &kNS_SHELLSERVICE_CID },
 #endif
     { NS_FEEDSNIFFER_CONTRACTID, &kNS_FEEDSNIFFER_CID },
-#ifdef MOZ_SAFE_BROWSING
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "blocked", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
-#endif
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "certerror", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "socialerror", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "providerdirectory", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "tabcrashed", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "feeds", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "privatebrowsing", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "rights", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },
     { NS_ABOUT_MODULE_CONTRACTID_PREFIX "robots", &kNS_BROWSER_ABOUT_REDIRECTOR_CID },

--- a/browser/components/moz.build
+++ b/browser/components/moz.build
@@ -45,23 +45,21 @@ EXTRA_COMPONENTS += [
     'nsBrowserGlue.js',
 ]
 
 EXTRA_JS_MODULES += [
     'distribution.js',
 ]
 
 BROWSER_CHROME_MANIFESTS += [
+    'safebrowsing/content/test/browser.ini',
     'tests/browser/browser.ini'
 ]
 
 XPCSHELL_TESTS_MANIFESTS += [
     'tests/unit/xpcshell.ini'
 ]
 
-if CONFIG['MOZ_SAFE_BROWSING']:
-    BROWSER_CHROME_MANIFESTS += ['safebrowsing/content/test/browser.ini']
-
 with Files('safebrowsing/*'):
     BUG_COMPONENT = ('Toolkit', 'Phishing Protection')
 
 with Files('controlcenter/**'):
     BUG_COMPONENT = ('Firefox', 'General')

--- a/browser/confvars.sh
+++ b/browser/confvars.sh
@@ -27,17 +27,16 @@ if test "$OS_ARCH" = "WINNT"; then
       fi
     fi
   fi
 fi
 
 # Enable building ./signmar and running libmar signature tests
 MOZ_ENABLE_SIGNMAR=1
 
-MOZ_SAFE_BROWSING=1
 MOZ_APP_VERSION=$FIREFOX_VERSION
 MOZ_APP_VERSION_DISPLAY=$FIREFOX_VERSION_DISPLAY
 MOZ_EXTENSIONS_DEFAULT=" gio"
 # MOZ_APP_DISPLAYNAME will be set by branding/configure.sh
 # MOZ_BRANDING_DIRECTORY is the default branding directory used when none is
 # specified. It should never point to the "official" branding directory.
 # For mozilla-beta, mozilla-release, or mozilla-central repositories, use
 # "unofficial" branding.

--- a/browser/installer/package-manifest.in
+++ b/browser/installer/package-manifest.in
@@ -591,23 +591,21 @@
 @RESPATH@/components/extensions-toolkit.manifest
 @RESPATH@/browser/components/extensions-browser.manifest
 
 ; Modules
 @RESPATH@/browser/modules/*
 @RESPATH@/modules/*
 
 ; Safe Browsing
-#ifdef MOZ_URL_CLASSIFIER
 @RESPATH@/components/nsURLClassifier.manifest
 @RESPATH@/components/nsUrlClassifierHashCompleter.js
 @RESPATH@/components/nsUrlClassifierListManager.js
 @RESPATH@/components/nsUrlClassifierLib.js
 @RESPATH@/components/url-classifier.xpt
-#endif
 
 ; Private Browsing
 @RESPATH@/components/privatebrowsing.xpt
 @RESPATH@/components/PrivateBrowsing.manifest
 @RESPATH@/components/PrivateBrowsingTrackingProtectionWhitelist.js
 
 ; Security Reports
 @RESPATH@/components/SecurityReporter.manifest

--- a/browser/locales/jar.mn
+++ b/browser/locales/jar.mn
@@ -48,20 +48,18 @@
     locale/browser/downloads/downloads.dtd         (%chrome/browser/downloads/downloads.dtd)
     locale/browser/downloads/downloads.properties  (%chrome/browser/downloads/downloads.properties)
     locale/browser/places/places.dtd               (%chrome/browser/places/places.dtd)
     locale/browser/places/places.properties        (%chrome/browser/places/places.properties)
     locale/browser/places/editBookmarkOverlay.dtd  (%chrome/browser/places/editBookmarkOverlay.dtd)
     locale/browser/places/bookmarkProperties.properties (%chrome/browser/places/bookmarkProperties.properties)
     locale/browser/preferences/selectBookmark.dtd  (%chrome/browser/preferences/selectBookmark.dtd)
     locale/browser/places/moveBookmarks.dtd        (%chrome/browser/places/moveBookmarks.dtd)
-#ifdef MOZ_SAFE_BROWSING
     locale/browser/safebrowsing/phishing-afterload-warning-message.dtd (%chrome/browser/safebrowsing/phishing-afterload-warning-message.dtd)
     locale/browser/safebrowsing/report-phishing.dtd                    (%chrome/browser/safebrowsing/report-phishing.dtd)
-#endif
     locale/browser/feeds/subscribe.dtd              (%chrome/browser/feeds/subscribe.dtd)
     locale/browser/feeds/subscribe.properties       (%chrome/browser/feeds/subscribe.properties)
     locale/browser/migration/migration.dtd         (%chrome/browser/migration/migration.dtd)
     locale/browser/migration/migration.properties  (%chrome/browser/migration/migration.properties)
     locale/browser/preferences/advanced.dtd           (%chrome/browser/preferences/advanced.dtd)
     locale/browser/preferences/applicationManager.dtd        (%chrome/browser/preferences/applicationManager.dtd)
     locale/browser/preferences/applicationManager.properties (%chrome/browser/preferences/applicationManager.properties)
     locale/browser/preferences/blocklists.dtd         (%chrome/browser/preferences/blocklists.dtd)

--- a/build/autoconf/android.m4
+++ b/build/autoconf/android.m4
@@ -216,18 +216,18 @@ if test -n "$MOZ_INSTALL_TRACKING"; then
     AC_SUBST(MOZ_INSTALL_TRACKING)
     MOZ_ANDROID_AAR(play-services-ads, $ANDROID_GOOGLE_PLAY_SERVICES_VERSION, google, com/google/android/gms)
     MOZ_ANDROID_AAR(play-services-basement, $ANDROID_GOOGLE_PLAY_SERVICES_VERSION, google, com/google/android/gms)
 fi
 
 ])
 
 dnl Configure an Android SDK.
-dnl Arg 1: target SDK version, like 22.
-dnl Arg 2: build tools version, like 22.0.1.
+dnl Arg 1: target SDK version, like 23.
+dnl Arg 2: list of build-tools versions, like "23.0.3 23.0.1".
 AC_DEFUN([MOZ_ANDROID_SDK],
 [
 
 MOZ_ARG_WITH_STRING(android-sdk,
 [  --with-android-sdk=DIR
                           location where the Android SDK can be found (like ~/.mozbuild/android-sdk-linux)],
     android_sdk_root=$withval)
 
@@ -249,22 +249,31 @@ case "$target" in
     android_target_sdk=$1
     AC_MSG_CHECKING([for Android SDK platform version $android_target_sdk])
     android_sdk=$android_sdk_root/platforms/android-$android_target_sdk
     if ! test -e "$android_sdk/source.properties" ; then
         AC_MSG_ERROR([You must download Android SDK platform version $android_target_sdk.  Try |mach bootstrap|.  (Looked for $android_sdk)])
     fi
     AC_MSG_RESULT([$android_sdk])
 
-    android_build_tools="$android_sdk_root"/build-tools/$2
-    AC_MSG_CHECKING([for Android build-tools version $2])
-    if test -d "$android_build_tools" -a -f "$android_build_tools/aapt"; then
-        AC_MSG_RESULT([$android_build_tools])
-    else
-        AC_MSG_ERROR([You must install the Android build-tools version $2.  Try |mach bootstrap|.  (Looked for $android_build_tools)])
+    AC_MSG_CHECKING([for Android build-tools])
+    android_build_tools_base="$android_sdk_root"/build-tools
+    android_build_tools_version=""
+    versions=($2)
+    for version in $versions; do
+        android_build_tools="$android_build_tools_base"/$version
+        if test -d "$android_build_tools" -a -f "$android_build_tools/aapt"; then
+            android_build_tools_version=$version
+            AC_MSG_RESULT([$android_build_tools])
+            break
+        fi
+    done
+    if test "$android_build_tools_version" == ""; then
+        version=$(echo $versions | cut -d" " -f1)
+        AC_MSG_ERROR([You must install the Android build-tools version $version.  Try |mach bootstrap|.  (Looked for "$android_build_tools_base"/$version)])
     fi
 
     MOZ_PATH_PROG(ZIPALIGN, zipalign, :, [$android_build_tools])
     MOZ_PATH_PROG(DX, dx, :, [$android_build_tools])
     MOZ_PATH_PROG(AAPT, aapt, :, [$android_build_tools])
     MOZ_PATH_PROG(AIDL, aidl, :, [$android_build_tools])
     if test -z "$ZIPALIGN" -o "$ZIPALIGN" = ":"; then
       AC_MSG_ERROR([The program zipalign was not found.  Try |mach bootstrap|.])
@@ -304,17 +313,17 @@ case "$target" in
     if test -z "$EMULATOR" -o "$EMULATOR" = ":"; then
       AC_MSG_ERROR([The program emulator was not found.  Try |mach bootstrap|.])
     fi
 
     ANDROID_TARGET_SDK="${android_target_sdk}"
     ANDROID_SDK="${android_sdk}"
     ANDROID_SDK_ROOT="${android_sdk_root}"
     ANDROID_TOOLS="${android_tools}"
-    ANDROID_BUILD_TOOLS_VERSION="$2"
+    ANDROID_BUILD_TOOLS_VERSION="$android_build_tools_version"
     AC_DEFINE_UNQUOTED(ANDROID_TARGET_SDK,$ANDROID_TARGET_SDK)
     AC_SUBST(ANDROID_TARGET_SDK)
     AC_SUBST(ANDROID_SDK_ROOT)
     AC_SUBST(ANDROID_SDK)
     AC_SUBST(ANDROID_TOOLS)
     AC_SUBST(ANDROID_BUILD_TOOLS_VERSION)
 
     MOZ_ANDROID_AAR(customtabs, $ANDROID_SUPPORT_LIBRARY_VERSION, android, com/android/support)

--- a/devtools/client/debugger/moz.build
+++ b/devtools/client/debugger/moz.build
@@ -8,9 +8,12 @@ DIRS += [
     'new'
 ]
 
 DevToolsModules(
     'debugger-commands.js',
     'panel.js'
 )
 
-BROWSER_CHROME_MANIFESTS += ['test/mochitest/browser.ini']
+BROWSER_CHROME_MANIFESTS += [
+  'new/test/mochitest/browser.ini',
+  'test/mochitest/browser.ini'
+]

new file mode 100644
--- /dev/null
+++ b/devtools/client/debugger/new/test/mochitest/browser.ini
@@ -0,0 +1,5 @@
+[DEFAULT]
+tags = devtools
+subsuite = devtools
+
+[browser_dbg_stub.js]

new file mode 100644
--- /dev/null
+++ b/devtools/client/debugger/new/test/mochitest/browser_dbg_stub.js
@@ -0,0 +1,7 @@
+
+add_task(function*() {
+  ok(true,
+     "This is a stub so that we can run the new debugger tests " +
+     "by copying them in here. This will go away once we land " +
+     "the initial suite of new tests");
+});

--- a/devtools/client/definitions.js
+++ b/devtools/client/definitions.js
@@ -177,24 +177,38 @@ Tools.jsdebugger = {
     return true;
   },
 
   build: function (iframeWindow, toolbox) {
     return new DebuggerPanel(iframeWindow, toolbox);
   }
 };
 
-if (Services.prefs.getBoolPref("devtools.debugger.new-debugger-frontend")) {
-  const NewDebuggerPanel = require("devtools/client/debugger/new/panel").DebuggerPanel;
+function switchDebugger() {
+  if (Services.prefs.getBoolPref("devtools.debugger.new-debugger-frontend")) {
+    const NewDebuggerPanel = require("devtools/client/debugger/new/panel").DebuggerPanel;
 
-  Tools.jsdebugger.url = "chrome://devtools/content/debugger/new/index.html";
-  Tools.jsdebugger.build = function (iframeWindow, toolbox) {
-    return new NewDebuggerPanel(iframeWindow, toolbox);
-  };
+    Tools.jsdebugger.url = "chrome://devtools/content/debugger/new/index.html";
+    Tools.jsdebugger.build = function (iframeWindow, toolbox) {
+      return new NewDebuggerPanel(iframeWindow, toolbox);
+    };
+  } else {
+    Tools.jsdebugger.url = "chrome://devtools/content/debugger/debugger.xul";
+    Tools.jsdebugger.build = function (iframeWindow, toolbox) {
+      return new DebuggerPanel(iframeWindow, toolbox);
+    };
+  }
 }
+switchDebugger();
+
+Services.prefs.addObserver(
+  "devtools.debugger.new-debugger-frontend",
+  { observe: switchDebugger },
+  false
+);
 
 Tools.styleEditor = {
   id: "styleeditor",
   key: l10n("open.commandkey", styleEditorStrings),
   ordinal: 4,
   visibilityswitch: "devtools.styleeditor.enabled",
   accesskey: l10n("open.accesskey", styleEditorStrings),
   modifiers: "shift",

--- a/devtools/client/shared/components/frame.js
+++ b/devtools/client/shared/components/frame.js
@@ -171,17 +171,18 @@ module.exports = createClass({
       let functionDisplayName = frame.functionDisplayName;
       if (!functionDisplayName && showAnonymousFunctionName) {
         functionDisplayName = webl10n.getStr("stacktrace.anonymousFunction");
       }
 
       if (functionDisplayName) {
         elements.push(
           dom.span({ className: "frame-link-function-display-name" },
-            functionDisplayName)
+            functionDisplayName),
+          " "
         );
       }
     }
 
     let displaySource = showFullSourceUrl ? long : short;
     if (isSourceMapped) {
       displaySource = getSourceMappedFile(displaySource);
     } else if (showEmptyPathAsHost && (displaySource === "" || displaySource === "/")) {
@@ -231,14 +232,14 @@ module.exports = createClass({
     } else {
       sourceEl = dom.span({
         className: "frame-link-source",
       }, sourceInnerEl);
     }
     elements.push(sourceEl);
 
     if (showHost && host) {
-      elements.push(dom.span({ className: "frame-link-host" }, host));
+      elements.push(" ", dom.span({ className: "frame-link-host" }, host));
     }
 
     return dom.span(attributes, ...elements);
   }
 });

--- a/devtools/client/shared/components/stack-trace.js
+++ b/devtools/client/shared/components/stack-trace.js
@@ -37,32 +37,32 @@ const StackTrace = createClass({
   },
 
   render() {
     let { stacktrace, onViewSourceInDebugger } = this.props;
 
     let frames = [];
     stacktrace.forEach(s => {
       if (s.asyncCause) {
-        frames.push(AsyncFrame({
+        frames.push("\t", AsyncFrame({
           asyncCause: s.asyncCause
-        }));
+        }), "\n");
       }
 
-      frames.push(Frame({
+      frames.push("\t", Frame({
         frame: {
           functionDisplayName: s.functionName,
           source: s.filename.split(" -> ").pop(),
           line: s.lineNumber,
           column: s.columnNumber,
         },
         showFunctionName: true,
         showAnonymousFunctionName: true,
         showFullSourceUrl: true,
         onClick: onViewSourceInDebugger
-      }));
+      }), "\n");
     });
 
     return dom.div({ className: "stack-trace" }, frames);
   }
 });
 
 module.exports = StackTrace;

--- a/devtools/client/shared/components/test/mochitest/test_stack-trace.html
+++ b/devtools/client/shared/components/test/mochitest/test_stack-trace.html
@@ -40,17 +40,19 @@ window.onload = function() {
     };
 
     let trace = ReactDOM.render(StackTrace(props), window.document.body);
     yield forceRender(trace);
 
     let traceEl = trace.getDOMNode();
     ok(traceEl, "Rendered StackTrace has an element");
 
-    let frameEls = traceEl.childNodes;
+    // Get the child nodes and filter out the text-only whitespace ones
+    let frameEls = Array.from(traceEl.childNodes)
+      .filter(n => n.className.includes("frame"));
     ok(frameEls, "Rendered StackTrace has frames");
     is(frameEls.length, 3, "StackTrace has 3 frames");
 
     // Check the top frame, function name should be anonymous
     checkFrameString({
       el: frameEls[0],
       functionName: "<anonymous>",
       source: "http://myfile.com/mahscripts.js",
@@ -71,13 +73,21 @@ window.onload = function() {
       functionName: "loadFunc",
       source: "http://myfile.com/loadee.js",
       file: "http://myfile.com/loadee.js",
       line: 10,
       column: null,
       shouldLink: true,
       tooltip: "View source in Debugger → http://myfile.com/loadee.js:10",
     });
+
+    // Check the tabs and newlines in the stack trace textContent
+    let traceText = traceEl.textContent;
+    let traceLines = traceText.split("\n");
+    ok(traceLines.length > 0, "There are newlines in the stack trace text");
+    is(traceLines.pop(), "", "There is a newline at the end of the stack trace text");
+    is(traceLines.length, 3, "The stack trace text has 3 lines");
+    ok(traceLines.every(l => l[0] == "\t"), "Every stack trace line starts with tab");
   });
 }
 </script>
 </body>
 </html>

--- a/devtools/client/webconsole/console-output.js
+++ b/devtools/client/webconsole/console-output.js
@@ -930,18 +930,16 @@ Messages.Simple.prototype = extend(Messa
       twisty.addEventListener("click", this._onClickCollapsible);
       this.element.appendChild(twisty);
       this.collapsible = true;
       this.element.setAttribute("collapsible", true);
     }
 
     this.element.appendChild(body);
 
-    this.element.appendChild(this.document.createTextNode("\n"));
-
     this.element.clipboardText = this.element.textContent;
 
     if (this.private) {
       this.element.setAttribute("private", true);
     }
 
     // TODO: handle object releasing in a more elegant way once all console
     // messages use the new API - bug 778766.
@@ -988,22 +986,26 @@ Messages.Simple.prototype = extend(Messa
 
     // do this before repeatNode is rendered - it has no effect afterwards
     this._repeatID.textContent += "|" + container.textContent;
 
     let repeatNode = this._renderRepeatNode();
     let location = this._renderLocation();
 
     if (repeatNode) {
+      bodyFlex.appendChild(this.document.createTextNode(" "));
       bodyFlex.appendChild(repeatNode);
     }
     if (location) {
+      bodyFlex.appendChild(this.document.createTextNode(" "));
       bodyFlex.appendChild(location);
     }
 
+    bodyFlex.appendChild(this.document.createTextNode("\n"));
+
     if (this.stack) {
       this._attachment = new Widgets.Stacktrace(this, this.stack).render().element;
     }
 
     if (this._attachment) {
       bodyWrapper.appendChild(this._attachment);
     }
 

--- a/devtools/client/webconsole/test/browser_console_copy_entire_message_context_menu.js
+++ b/devtools/client/webconsole/test/browser_console_copy_entire_message_context_menu.js
@@ -1,69 +1,97 @@
 /* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
 /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
+/* globals goDoCommand */
+
 "use strict";
 
 // Test copying of the entire console message when right-clicked
 // with no other text selected. See Bug 1100562.
 
-function test() {
+add_task(function* () {
   let hud;
   let outputNode;
   let contextMenu;
 
-  const TEST_URI = "http://example.com/browser/devtools/client/webconsole/" +
-                   "test/test-console.html";
-
-  Task.spawn(runner).then(finishTest);
+  const TEST_URI = "http://example.com/browser/devtools/client/webconsole/test/test-console.html";
 
-  function* runner() {
-    const {tab} = yield loadTab(TEST_URI);
-    hud = yield openConsole(tab);
-    outputNode = hud.outputNode;
-    contextMenu = hud.iframeWindow.document.getElementById("output-contextmenu");
+  const { tab, browser } = yield loadTab(TEST_URI);
+  hud = yield openConsole(tab);
+  outputNode = hud.outputNode;
+  contextMenu = hud.iframeWindow.document.getElementById("output-contextmenu");
+
+  registerCleanupFunction(() => {
+    hud = outputNode = contextMenu = null;
+  });
 
-    registerCleanupFunction(() => {
-      hud = outputNode = contextMenu = null;
-    });
+  hud.jsterm.clearOutput();
 
-    hud.jsterm.clearOutput();
-    content.console.log("bug 1100562");
+  yield ContentTask.spawn(browser, {}, function* () {
+    let button = content.document.getElementById("testTrace");
+    button.click();
+  });
 
-    let [results] = yield waitForMessages({
-      webconsole: hud,
-      messages: [{
+  let results = yield waitForMessages({
+    webconsole: hud,
+    messages: [
+      {
         text: "bug 1100562",
         category: CATEGORY_WEBDEV,
         severity: SEVERITY_LOG,
-      }]
-    });
+        lines: 1,
+      },
+      {
+        name: "console.trace output",
+        consoleTrace: true,
+        lines: 3,
+      },
+    ]
+  });
 
-    outputNode.focus();
-    let message = [...results.matched][0];
+  outputNode.focus();
 
-    yield waitForContextMenu(contextMenu, message, copyFromPopup,
-                             testContextMenuCopy);
+  for (let result of results) {
+    let message = [...result.matched][0];
 
-    function copyFromPopup() {
+    yield waitForContextMenu(contextMenu, message, () => {
       let copyItem = contextMenu.querySelector("#cMenu_copy");
       copyItem.doCommand();
 
       let controller = top.document.commandDispatcher
                                    .getControllerForCommand("cmd_copy");
       is(controller.isCommandEnabled("cmd_copy"), true, "cmd_copy is enabled");
-    }
+    });
+
+    let clipboardText;
+
+    yield waitForClipboardPromise(
+      () => goDoCommand("cmd_copy"),
+      (str) => {
+        clipboardText = str;
+        return message.textContent == clipboardText;
+      }
+    );
+
+    ok(clipboardText, "Clipboard text was found and saved");
 
-    function testContextMenuCopy() {
-      waitForClipboard((str) => {
-        return message.textContent.trim() == str.trim();
-      }, () => {
-        goDoCommand("cmd_copy");
-      }, () => {}, () => {}
-      );
+    let lines = clipboardText.split("\n");
+    ok(lines.length > 0, "There is at least one newline in the message");
+    is(lines.pop(), "", "There is a newline at the end");
+    is(lines.length, result.lines, `There are ${result.lines} lines in the message`);
+
+    // Test the first line for "timestamp message repeat file:line"
+    let firstLine = lines.shift();
+    ok(/^[\d:.]+ .+ \d+ .+:\d+$/.test(firstLine),
+      "The message's first line has the right format");
+
+    // Test the remaining lines (stack trace) for "TABfunctionName sourceURL:line:col"
+    for (let line of lines) {
+      ok(/^\t.+ .+:\d+:\d+$/.test(line), "The stack trace line has the right format");
     }
+  }
 
-    yield closeConsole(tab);
-  }
-}
+  yield closeConsole(tab);
+  yield finishTest();
+});

--- a/devtools/client/webconsole/test/test-console.html
+++ b/devtools/client/webconsole/test/test-console.html
@@ -8,20 +8,27 @@
       };
 
       function test() {
         var str = "Dolske Digs Bacon, Now and Forevermore."
         for (var i=0; i < 5; i++) {
           console.log(str);
         }
       }
+
+      function testTrace() {
+        console.log("bug 1100562");
+        console.trace();
+      }
+
       console.info("INLINE SCRIPT:");
       test();
       console.warn("I'm warning you, he will eat up all yr bacon.");
       console.error("Error Message");
     </script>
   </head>
   <body>
     <h1 id="header">Heads Up Display Demo</h1>
     <button onclick="test();">Log stuff about Dolske</button>
+    <button id="testTrace" onclick="testTrace();">Log stuff with stacktrace</button>
     <div id="myDiv"></div>
   </body>
 </html>

--- a/devtools/shared/l10n.js
+++ b/devtools/shared/l10n.js
@@ -1,44 +1,55 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
 const parsePropertiesFile = require("devtools/shared/node-properties/node-properties");
 const { sprintf } = require("devtools/shared/sprintfjs/sprintf");
 
+const propertiesMap = {};
+
+/**
+ * Memoized getter for properties files that ensures a given url is only required and
+ * parsed once.
+ *
+ * @param {String} url
+ *        The URL of the properties file to parse.
+ * @return {Object} parsed properties mapped in an object.
+ */
+function getProperties(url) {
+  if (!propertiesMap[url]) {
+    propertiesMap[url] = parsePropertiesFile(require(`raw!${url}`));
+  }
+
+  return propertiesMap[url];
+}
+
 /**
  * Localization convenience methods.
  *
  * @param string stringBundleName
  *        The desired string bundle's name.
  */
 function LocalizationHelper(stringBundleName) {
   this.stringBundleName = stringBundleName;
 }
 
 LocalizationHelper.prototype = {
-  get properties() {
-    if (!this._properties) {
-      this._properties = parsePropertiesFile(require(`raw!${this.stringBundleName}`));
-    }
-
-    return this._properties;
-  },
-
   /**
    * L10N shortcut function.
    *
    * @param string name
    * @return string
    */
   getStr: function (name) {
-    if (name in this.properties) {
-      return this.properties[name];
+    let properties = getProperties(this.stringBundleName);
+    if (name in properties) {
+      return properties[name];
     }
 
     throw new Error("No localization found for [" + name + "]");
   },
 
   /**
    * L10N shortcut function.
    *
@@ -98,16 +109,73 @@ LocalizationHelper.prototype = {
 
     return number.toLocaleString(undefined, {
       maximumFractionDigits: decimals,
       minimumFractionDigits: decimals
     });
   }
 };
 
+function getPropertiesForNode(node) {
+  let bundleEl = node.closest("[data-localization-bundle]");
+  if (!bundleEl) {
+    return null;
+  }
+
+  let propertiesUrl = bundleEl.getAttribute("data-localization-bundle");
+  return getProperties(propertiesUrl);
+}
+
+/**
+ * Translate existing markup annotated with data-localization attributes.
+ *
+ * How to use data-localization in markup:
+ *
+ *   <div data-localization="content=myContent;title=myTitle"/>
+ *
+ * The data-localization attribute identifies an element as being localizable.
+ * The content of the attribute is semi-colon separated list of descriptors.
+ * - "title=myTitle" means the "title" attribute should be replaced with the localized
+ *   string corresponding to the key "myTitle".
+ * - "content=myContent" means the text content of the node should be replaced by the
+ *   string corresponding to "myContent"
+ *
+ * How to define the localization bundle in markup:
+ *
+ *   <div data-localization-bundle="url/to/my.properties">
+ *     [...]
+ *       <div data-localization="content=myContent;title=myTitle"/>
+ *
+ * Set the data-localization-bundle on an ancestor of the nodes that should be localized.
+ *
+ * @param {Element} root
+ *        The root node to use for the localization
+ */
+function localizeMarkup(root) {
+  let elements = root.querySelectorAll("[data-localization]");
+  for (let element of elements) {
+    let properties = getPropertiesForNode(element);
+    if (!properties) {
+      continue;
+    }
+
+    let attributes = element.getAttribute("data-localization").split(";");
+    for (let attribute of attributes) {
+      let [name, value] = attribute.trim().split("=");
+      if (name === "content") {
+        element.textContent = properties[value];
+      } else {
+        element.setAttribute(name, properties[value]);
+      }
+    }
+
+    element.removeAttribute("data-localization");
+  }
+}
+
 const sharedL10N = new LocalizationHelper("devtools-shared/locale/shared.properties");
 const ELLIPSIS = sharedL10N.getStr("ellipsis");
 
 /**
  * A helper for having the same interface as LocalizationHelper, but for more
  * than one file. Useful for abstracting l10n string locations.
  */
 function MultiLocalizationHelper(...stringBundleNames) {
@@ -135,10 +203,11 @@ function MultiLocalizationHelper(...stri
           }
         }
         return null;
       };
     });
 }
 
 exports.LocalizationHelper = LocalizationHelper;
+exports.localizeMarkup = localizeMarkup;
 exports.MultiLocalizationHelper = MultiLocalizationHelper;
 exports.ELLIPSIS = ELLIPSIS;

--- a/devtools/shared/tests/browser/browser.ini
+++ b/devtools/shared/tests/browser/browser.ini
@@ -1,7 +1,8 @@
 [DEFAULT]
 tags = devtools
 subsuite = devtools
 support-files =
   ../../../server/tests/browser/head.js
 
 [browser_async_storage.js]
+[browser_l10n_localizeMarkup.js]

new file mode 100644
--- /dev/null
+++ b/devtools/shared/tests/browser/browser_l10n_localizeMarkup.js
@@ -0,0 +1,54 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Tests that the markup localization works properly.
+
+const { localizeMarkup, LocalizationHelper } = require("devtools/shared/l10n");
+
+add_task(function* () {
+  info("Check that the strings used for this test are still valid");
+  let INSPECTOR_L10N = new LocalizationHelper("devtools/locale/inspector.properties");
+  let TOOLBOX_L10N = new LocalizationHelper("devtools/locale/toolbox.properties");
+  let str1 = INSPECTOR_L10N.getStr("inspector.label");
+  let str2 = INSPECTOR_L10N.getStr("inspector.commandkey");
+  let str3 = TOOLBOX_L10N.getStr("toolbox.defaultTitle");
+  ok(str1 && str2 && str3, "If this failed, strings should be updated in the test");
+
+  info("Create the test markup");
+  let div = document.createElement("div");
+  div.innerHTML =
+  `<div data-localization-bundle="devtools/locale/inspector.properties">
+     <div id="d0" data-localization="content=inspector.someInvalidKey"></div>
+     <div id="d1" data-localization="content=inspector.label">Text will disappear</div>
+     <div id="d2" data-localization="content=inspector.label;title=inspector.commandkey">
+     </div>
+     <!-- keep the following data-localization on two separate lines -->
+     <div id="d3" data-localization="content=inspector.label;
+                                     title=inspector.commandkey"></div>
+     <div id="d4" data-localization="aria-label=inspector.label">Some content</div>
+     <div data-localization-bundle="devtools/locale/toolbox.properties">
+       <div id="d5" data-localization="content=toolbox.defaultTitle"></div>
+     </div>
+   </div>
+  `;
+
+  info("Use localization helper to localize the test markup");
+  localizeMarkup(div);
+
+  let div1 = div.querySelector("#d1");
+  let div2 = div.querySelector("#d2");
+  let div3 = div.querySelector("#d3");
+  let div4 = div.querySelector("#d4");
+  let div5 = div.querySelector("#d5");
+
+  is(div1.innerHTML, str1, "The content of #d1 is localized");
+  is(div2.innerHTML, str1, "The content of #d2 is localized");
+  is(div2.getAttribute("title"), str2, "The title of #d2 is localized");
+  is(div3.innerHTML, str1, "The content of #d3 is localized");
+  is(div3.getAttribute("title"), str2, "The title of #d3 is localized");
+  is(div4.innerHTML, "Some content", "The content of #d4 is not replaced");
+  is(div4.getAttribute("aria-label"), str1, "The aria-label of #d4 is localized");
+  is(div5.innerHTML, str3, "The content of #d5 is localized with another bundle");
+});

--- a/dom/animation/AnimationEffectReadOnly.cpp
+++ b/dom/animation/AnimationEffectReadOnly.cpp
@@ -138,39 +138,45 @@ AnimationEffectReadOnly::GetComputedTimi
   }
   const TimeDuration& localTime = aLocalTime.Value();
 
   // Calculate the time within the active interval.
   // https://w3c.github.io/web-animations/#active-time
   StickyTimeDuration activeTime;
 
   StickyTimeDuration beforeActiveBoundary =
-    std::min(StickyTimeDuration(aTiming.mDelay), result.mEndTime);
+    std::max(std::min(StickyTimeDuration(aTiming.mDelay), result.mEndTime),
+             zeroDuration);
+
   StickyTimeDuration activeAfterBoundary =
-    std::min(StickyTimeDuration(aTiming.mDelay + result.mActiveDuration),
-             result.mEndTime);
+    std::max(std::min(StickyTimeDuration(aTiming.mDelay +
+                                         result.mActiveDuration),
+                      result.mEndTime),
+             zeroDuration);
 
   if (localTime > activeAfterBoundary ||
       (aPlaybackRate >= 0 && localTime == activeAfterBoundary)) {
     result.mPhase = ComputedTiming::AnimationPhase::After;
     if (!result.FillsForwards()) {
       // The animation isn't active or filling at this time.
       return result;
     }
-    activeTime = std::max(std::min(result.mActiveDuration,
-                                   result.mActiveDuration + aTiming.mEndDelay),
-                          zeroDuration);
+    activeTime =
+      std::max(std::min(StickyTimeDuration(localTime - aTiming.mDelay),
+                        result.mActiveDuration),
+               zeroDuration);
   } else if (localTime < beforeActiveBoundary ||
              (aPlaybackRate < 0 && localTime == beforeActiveBoundary)) {
     result.mPhase = ComputedTiming::AnimationPhase::Before;
     if (!result.FillsBackwards()) {
       // The animation isn't active or filling at this time.
       return result;
     }
-    // activeTime is zero
+    activeTime = std::max(StickyTimeDuration(localTime - aTiming.mDelay),
+                          zeroDuration);
   } else {
     MOZ_ASSERT(result.mActiveDuration != zeroDuration,
                "How can we be in the middle of a zero-duration interval?");
     result.mPhase = ComputedTiming::AnimationPhase::Active;
     activeTime = localTime - aTiming.mDelay;
   }
 
   // Convert active time to a multiple of iterations.

--- a/dom/animation/TimingParams.h
+++ b/dom/animation/TimingParams.h
@@ -109,17 +109,18 @@ struct TimingParams
       return zeroDuration;
     }
 
     return mDuration->MultDouble(mIterations);
   }
 
   StickyTimeDuration EndTime() const
   {
-    return mDelay + ActiveDuration() + mEndDelay;
+    return std::max(mDelay + ActiveDuration() + mEndDelay,
+                    StickyTimeDuration());
   }
 
   bool operator==(const TimingParams& aOther) const;
   bool operator!=(const TimingParams& aOther) const
   {
     return !(*this == aOther);
   }
 };

--- a/dom/animation/test/css-animations/file_animation-computed-timing.html
+++ b/dom/animation/test/css-animations/file_animation-computed-timing.html
@@ -187,17 +187,17 @@ test(function(t) {
                 'Initial value of endTime');
 }, 'endTime of an infinitely repeating zero-duration animation');
 
 test(function(t) {
   // Fill forwards so div.getAnimations()[0] won't return an
   // undefined value.
   var div = addDiv(t, {style: 'animation: moveAnimation 10s -100s forwards'});
   var effect = div.getAnimations()[0].effect;
-  assert_equals(effect.getComputedTiming().endTime, -90 * MS_PER_SEC,
+  assert_equals(effect.getComputedTiming().endTime, 0,
                 'Initial value of endTime');
 }, 'endTime of an animation that finishes before its startTime');
 
 
 // --------------------
 // activeDuration
 // = iteration duration * iteration count
 // --------------------

--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -274,61 +274,76 @@ public:
                                                 NS_LITERAL_STRING("error"),
                                                 false,
                                                 false);
   }
 };
 
 /**
  * This listener observes the first video frame to arrive with a non-empty size,
- * and calls HTMLMediaElement::ReceivedMediaStreamInitialSize() with that size.
+ * and calls HTMLMediaElement::UpdateInitialMediaSize() with that size.
  */
 class HTMLMediaElement::StreamSizeListener : public DirectMediaStreamTrackListener {
 public:
   explicit StreamSizeListener(HTMLMediaElement* aElement) :
     mElement(aElement),
     mInitialSizeFound(false)
   {}
+
   void Forget() { mElement = nullptr; }
 
   void ReceivedSize(gfx::IntSize aSize)
   {
+    MOZ_ASSERT(NS_IsMainThread());
+
     if (!mElement) {
       return;
     }
+
     RefPtr<HTMLMediaElement> deathGrip = mElement;
     mElement->UpdateInitialMediaSize(aSize);
   }
 
   void NotifyRealtimeTrackData(MediaStreamGraph* aGraph,
                                StreamTime aTrackOffset,
                                const MediaSegment& aMedia) override
   {
-    if (mInitialSizeFound || aMedia.GetType() != MediaSegment::VIDEO) {
+    if (mInitialSizeFound) {
       return;
     }
+
+    if (aMedia.GetType() != MediaSegment::VIDEO) {
+      MOZ_ASSERT(false, "Should only lock on to a video track");
+      return;
+    }
+
     const VideoSegment& video = static_cast<const VideoSegment&>(aMedia);
     for (VideoSegment::ConstChunkIterator c(video); !c.IsEnded(); c.Next()) {
       if (c->mFrame.GetIntrinsicSize() != gfx::IntSize(0,0)) {
         mInitialSizeFound = true;
         nsCOMPtr<nsIRunnable> event =
-          NewRunnableMethod<gfx::IntSize>(
-              this, &StreamSizeListener::ReceivedSize,
-              c->mFrame.GetIntrinsicSize());
-        aGraph->DispatchToMainThreadAfterStreamStateUpdate(event.forget());
+          NewRunnableMethod<gfx::IntSize>(this, &StreamSizeListener::ReceivedSize,
+                                          c->mFrame.GetIntrinsicSize());
+        // This is fine to dispatch straight to main thread (instead of via
+        // ...AfterStreamUpdate()) since it reflects state of the element,
+        // not the stream. Events reflecting stream or track state should be
+        // dispatched so their order is preserved.
+        NS_DispatchToMainThread(event.forget());
         return;
       }
     }
   }
 
 private:
   // These fields may only be accessed on the main thread
   HTMLMediaElement* mElement;
 
-  // These fields may only be accessed on the MSG thread
+  // These fields may only be accessed on the MSG's appending thread.
+  // (this is a direct listener so we get called by whoever is producing
+  // this track's data)
   bool mInitialSizeFound;
 };
 
 /**
  * There is a reference cycle involving this class: MediaLoadListener
  * holds a reference to the HTMLMediaElement, which holds a reference
  * to an nsIChannel, which holds a reference to this listener.
  * We break the reference cycle in OnStartRequest by clearing mElement.
@@ -2570,26 +2585,31 @@ HTMLMediaElement::CaptureStreamInternal(
     }
 
     // mAudioCaptured tells the user that the audio played by this media element
     // is being routed to the captureStreams *instead* of being played to
     // speakers.
     mAudioCaptured = true;
   }
 
+  if (mDecoder) {
+    out->mCapturingDecoder = true;
+    mDecoder->AddOutputStream(out->mStream->GetInputStream()->AsProcessedStream(),
+                              aFinishWhenEnded);
+  } else if (mSrcStream) {
+    out->mCapturingMediaStream = true;
+  }
+
   if (mReadyState == HAVE_NOTHING) {
-    // Do not expose the tracks directly before we have metadata.
+    // Do not expose the tracks until we have metadata.
     RefPtr<DOMMediaStream> result = out->mStream;
     return result.forget();
   }
 
   if (mDecoder) {
-    out->mCapturingDecoder = true;
-    mDecoder->AddOutputStream(out->mStream->GetInputStream()->AsProcessedStream(),
-                              aFinishWhenEnded);
     if (HasAudio()) {
       TrackID audioTrackId = mMediaInfo.mAudio.mTrackId;
       RefPtr<MediaStreamTrackSource> trackSource =
         getter->GetMediaStreamTrackSource(audioTrackId);
       RefPtr<MediaStreamTrack> track =
         out->mStream->CreateDOMTrack(audioTrackId, MediaSegment::AUDIO,
                                      trackSource);
       out->mStream->AddTrackInternal(track);
@@ -2605,32 +2625,16 @@ HTMLMediaElement::CaptureStreamInternal(
                                      trackSource);
       out->mStream->AddTrackInternal(track);
       LOG(LogLevel::Debug,
           ("Created video track %d for captured decoder", videoTrackId));
     }
   }
 
   if (mSrcStream) {
-    out->mCapturingMediaStream = true;
-    MediaStream* inputStream = out->mStream->GetInputStream();
-    if (!inputStream) {
-      NS_ERROR("No input stream");
-      RefPtr<DOMMediaStream> result = out->mStream;
-      return result.forget();
-    }
-
-    ProcessedMediaStream* processedInputStream =
-      inputStream->AsProcessedStream();
-    if (!processedInputStream) {
-      NS_ERROR("Input stream not a ProcessedMediaStream");
-      RefPtr<DOMMediaStream> result = out->mStream;
-      return result.forget();
-    }
-
     for (size_t i = 0; i < AudioTracks()->Length(); ++i) {
       AudioTrack* t = (*AudioTracks())[i];
       if (t->Enabled()) {
         AddCaptureMediaTrackToOutputStream(t, *out, false);
       }
     }
     if (IsVideo() && !out->mCapturingAudioOnly) {
       // Only add video tracks if we're a video element and the output stream

--- a/dom/ipc/TabParent.cpp
+++ b/dom/ipc/TabParent.cpp
@@ -2549,17 +2549,17 @@ TabParent::GetAuthPrompt(uint32_t aPromp
   // of the dialogs works as it should when using tabs.
   nsCOMPtr<nsISupports> prompt;
   rv = wwatch->GetPrompt(window, iid, getter_AddRefs(prompt));
   NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsILoginManagerPrompter> prompter = do_QueryInterface(prompt);
   if (prompter) {
     nsCOMPtr<nsIDOMElement> browser = do_QueryInterface(mFrameElement);
-    prompter->SetE10sData(browser, nullptr);
+    prompter->SetBrowser(browser);
   }
 
   *aResult = prompt.forget().take();
   return NS_OK;
 }
 
 PColorPickerParent*
 TabParent::AllocPColorPickerParent(const nsString& aTitle,

--- a/dom/media/MediaDecoderStateMachine.cpp
+++ b/dom/media/MediaDecoderStateMachine.cpp
@@ -237,17 +237,16 @@ MediaDecoderStateMachine::MediaDecoderSt
   mIsVideoPrerolling(false),
   mAudioCaptured(false),
   INIT_WATCHABLE(mAudioCompleted, false),
   INIT_WATCHABLE(mVideoCompleted, false),
   mNotifyMetadataBeforeFirstFrame(false),
   mQuickBuffering(false),
   mMinimizePreroll(false),
   mDecodeThreadWaiting(false),
-  mDecodingFirstFrame(true),
   mSentLoadedMetadataEvent(false),
   mSentFirstFrameLoadedEvent(false),
   mSentPlaybackEndedEvent(false),
   mVideoDecodeSuspended(false),
   mVideoDecodeSuspendTimer(mTaskQueue),
   mOutputStreamManager(new OutputStreamManager()),
   mResource(aDecoder->GetResource()),
   mAudioOffloading(false),
@@ -483,25 +482,26 @@ bool MediaDecoderStateMachine::HaveEnoug
 bool
 MediaDecoderStateMachine::NeedToDecodeVideo()
 {
   MOZ_ASSERT(OnTaskQueue());
   SAMPLE_LOG("NeedToDecodeVideo() isDec=%d minPrl=%d enufVid=%d",
              IsVideoDecoding(), mMinimizePreroll, HaveEnoughDecodedVideo());
   return IsVideoDecoding() &&
          mState != DECODER_STATE_SEEKING &&
-         ((IsDecodingFirstFrame() && VideoQueue().GetSize() == 0) ||
+         ((!mSentFirstFrameLoadedEvent && VideoQueue().GetSize() == 0) ||
           (!mMinimizePreroll && !HaveEnoughDecodedVideo()));
 }
 
 bool
 MediaDecoderStateMachine::NeedToSkipToNextKeyframe()
 {
   MOZ_ASSERT(OnTaskQueue());
-  if (IsDecodingFirstFrame()) {
+  // Don't skip when we're still decoding first frames.
+  if (!mSentFirstFrameLoadedEvent) {
     return false;
   }
   MOZ_ASSERT(mState == DECODER_STATE_DECODING ||
              mState == DECODER_STATE_BUFFERING ||
              mState == DECODER_STATE_SEEKING);
 
   // Since GetClock() can only be called after starting MediaSink, we return
   // false quickly if it is not started because we won't fall behind playback
@@ -552,17 +552,17 @@ bool
 MediaDecoderStateMachine::NeedToDecodeAudio()
 {
   MOZ_ASSERT(OnTaskQueue());
   SAMPLE_LOG("NeedToDecodeAudio() isDec=%d minPrl=%d enufAud=%d",
              IsAudioDecoding(), mMinimizePreroll, HaveEnoughDecodedAudio());
 
   return IsAudioDecoding() &&
          mState != DECODER_STATE_SEEKING &&
-         ((IsDecodingFirstFrame() && AudioQueue().GetSize() == 0) ||
+         ((!mSentFirstFrameLoadedEvent && AudioQueue().GetSize() == 0) ||
           (!mMinimizePreroll && !HaveEnoughDecodedAudio()));
 }
 
 void
 MediaDecoderStateMachine::OnAudioDecoded(MediaData* aAudioSample)
 {
   MOZ_ASSERT(OnTaskQueue());
   MOZ_ASSERT(mState != DECODER_STATE_SEEKING);
@@ -728,17 +728,17 @@ MediaDecoderStateMachine::OnNotDecoded(M
     }
   }
 }
 
 bool
 MediaDecoderStateMachine::MaybeFinishDecodeFirstFrame()
 {
   MOZ_ASSERT(OnTaskQueue());
-  if (!IsDecodingFirstFrame() ||
+  if (mSentFirstFrameLoadedEvent ||
       (IsAudioDecoding() && AudioQueue().GetSize() == 0) ||
       (IsVideoDecoding() && VideoQueue().GetSize() == 0)) {
     return false;
   }
   FinishDecodeFirstFrame();
   if (!mQueuedSeek.Exists()) {
     return false;
   }
@@ -785,17 +785,17 @@ MediaDecoderStateMachine::OnVideoDecoded
       // arrive, increase the amount of audio we buffer to ensure that we
       // don't run out of audio. This is unnecessary for async readers,
       // since they decode audio and video on different threads so they
       // are unlikely to run out of decoded audio.
       if (mReader->IsAsync()) {
         return;
       }
       TimeDuration decodeTime = TimeStamp::Now() - aDecodeStartTime;
-      if (!IsDecodingFirstFrame() &&
+      if (mSentFirstFrameLoadedEvent &&
           THRESHOLD_FACTOR * DurationToUsecs(decodeTime) > mLowAudioThresholdUsecs &&
           !HasLowUndecodedData())
       {
         mLowAudioThresholdUsecs =
           std::min(THRESHOLD_FACTOR * DurationToUsecs(decodeTime), mAmpleAudioThresholdUsecs);
         mAmpleAudioThresholdUsecs = std::max(THRESHOLD_FACTOR * mLowAudioThresholdUsecs,
                                               mAmpleAudioThresholdUsecs);
         DECODER_LOG("Slow video decode, set mLowAudioThresholdUsecs=%lld mAmpleAudioThresholdUsecs=%lld",
@@ -1072,17 +1072,16 @@ MediaDecoderStateMachine::ExitState(Stat
 }
 
 void
 MediaDecoderStateMachine::EnterState(State aState)
 {
   MOZ_ASSERT(OnTaskQueue());
   switch (aState) {
     case DECODER_STATE_DECODING_METADATA:
-      mDecodingFirstFrame = true;
       ReadMetadata();
       break;
     case DECODER_STATE_DORMANT:
       DiscardSeekTaskIfExist();
       if (IsPlaying()) {
         StopPlayback();
       }
       Reset();
@@ -1255,29 +1254,21 @@ MediaDecoderStateMachine::Shutdown()
 }
 
 void
 MediaDecoderStateMachine::StartDecoding()
 {
   MOZ_ASSERT(OnTaskQueue());
   MOZ_ASSERT(mState == DECODER_STATE_DECODING);
 
-  if (mDecodingFirstFrame && mSentFirstFrameLoadedEvent) {
-    // We're resuming from dormant state, so we don't need to request
-    // the first samples in order to determine the media start time,
-    // we have the start time from last time we loaded.
-    // FinishDecodeFirstFrame will be launched upon completion of the seek when
-    // we have data ready to play.
-    MOZ_ASSERT(mQueuedSeek.Exists() && mSentFirstFrameLoadedEvent,
-               "Return from dormant must have queued seek");
-
-    if (mQueuedSeek.Exists()) {
-      InitiateSeek(Move(mQueuedSeek));
-      return;
-    }
+  // Handle the pending seek now if we've decoded first frames. Otherwise it
+  // will be handled after decoding first frames.
+  if (mSentFirstFrameLoadedEvent && mQueuedSeek.Exists()) {
+    InitiateSeek(Move(mQueuedSeek));
+    return;
   }
 
   if (CheckIfDecodeComplete()) {
     SetState(DECODER_STATE_COMPLETED);
     return;
   }
 
   mDecodeStartTime = TimeStamp::Now();
@@ -1506,18 +1497,22 @@ MediaDecoderStateMachine::Seek(SeekTarge
   if (aTarget.IsNextFrame() && !HasVideo()) {
     DECODER_WARN("Ignore a NextFrameSeekTask on a media file without video track.");
     return MediaDecoder::SeekPromise::CreateAndReject(/* aIgnored = */ true, __func__);
   }
 
   MOZ_ASSERT(mState > DECODER_STATE_DECODING_METADATA,
                "We should have got duration already");
 
-  if (mState < DECODER_STATE_DECODING ||
-      (IsDecodingFirstFrame() && !mReader->ForceZeroStartTime())) {
+  // Can't seek until the start time is known.
+  bool hasStartTime = mSentFirstFrameLoadedEvent || mReader->ForceZeroStartTime();
+  // Can't seek when state is WAIT_FOR_CDM or DORMANT.
+  bool stateAllowed = mState >= DECODER_STATE_DECODING;
+
+  if (!stateAllowed || !hasStartTime) {
     DECODER_LOG("Seek() Not Enough Data to continue at this stage, queuing seek");
     mQueuedSeek.RejectIfExists(__func__);
     mQueuedSeek.mTarget = aTarget;
     return mQueuedSeek.mPromise.Ensure(__func__);
   }
   mQueuedSeek.RejectIfExists(__func__);
 
   DECODER_LOG("Changed state to SEEKING (to %lld)", aTarget.GetTime().ToMicroseconds());
@@ -1901,18 +1896,18 @@ bool MediaDecoderStateMachine::HasLowUnd
 {
   MOZ_ASSERT(OnTaskQueue());
   return HasLowUndecodedData(mLowDataThresholdUsecs);
 }
 
 bool MediaDecoderStateMachine::HasLowUndecodedData(int64_t aUsecs)
 {
   MOZ_ASSERT(OnTaskQueue());
-  NS_ASSERTION(mState >= DECODER_STATE_DECODING && !IsDecodingFirstFrame(),
-               "Must have loaded first frame for mBuffered to be valid");
+  MOZ_ASSERT(mState >= DECODER_STATE_DECODING && mSentFirstFrameLoadedEvent,
+             "Must have loaded first frame for mBuffered to be valid");
 
   // If we don't have a duration, mBuffered is probably not going to have
   // a useful buffered range. Return false here so that we don't get stuck in
   // buffering mode for live streams.
   if (Duration().IsInfinite()) {
     return false;
   }
 
@@ -2069,22 +2064,16 @@ MediaDecoderStateMachine::EnqueueFirstFr
                              : MediaDecoderEventVisibility::Observable;
       self->mFirstFrameLoadedEvent.Notify(
         nsAutoPtr<MediaInfo>(new MediaInfo(self->mInfo)), visibility);
     },
     // Reject
     []() { MOZ_CRASH("Should not reach"); }));
 }
 
-bool
-MediaDecoderStateMachine::IsDecodingFirstFrame()
-{
-  return mState == DECODER_STATE_DECODING && mDecodingFirstFrame;
-}
-
 void
 MediaDecoderStateMachine::FinishDecodeFirstFrame()
 {
   MOZ_ASSERT(OnTaskQueue());
   DECODER_LOG("FinishDecodeFirstFrame");
 
   if (!mSentFirstFrameLoadedEvent) {
     mMediaSink->Redraw(mInfo.mVideo);
@@ -2101,19 +2090,18 @@ MediaDecoderStateMachine::FinishDecodeFi
 
   // Get potentially updated metadata
   mReader->ReadUpdatedMetadata(&mInfo);
 
   if (!mNotifyMetadataBeforeFirstFrame) {
     // If we didn't have duration and/or start time before, we should now.
     EnqueueLoadedMetadataEvent();
   }
+
   EnqueueFirstFrameLoadedEvent();
-
-  mDecodingFirstFrame = false;
 }
 
 void
 MediaDecoderStateMachine::SeekCompleted()
 {
   MOZ_ASSERT(OnTaskQueue());
   MOZ_ASSERT(mState == DECODER_STATE_SEEKING);
 
@@ -2168,19 +2156,21 @@ MediaDecoderStateMachine::SeekCompleted(
   // Reset the MediaDecoderReaderWrapper's callbask.
   DiscardSeekTaskIfExist();
 
   // NOTE: Discarding the mSeekTask must be done before here. The following code
   // might ask the MediaDecoderReaderWrapper to request media data, however, the
   // SeekTask::Discard() will ask MediaDecoderReaderWrapper to discard media
   // data requests.
 
-  if (mDecodingFirstFrame) {
-    // We were resuming from dormant, or initiated a seek early.
-    // We can fire loadeddata now.
+  // Notify FirstFrameLoaded now if we haven't since we've decoded some data
+  // for readyState to transition to HAVE_CURRENT_DATA and fire 'loadeddata'.
+  if (!mSentFirstFrameLoadedEvent) {
+    // Only MSE can start seeking before finishing decoding first frames.
+    MOZ_ASSERT(mReader->ForceZeroStartTime());
     FinishDecodeFirstFrame();
   }
 
   // Ensure timestamps are up to date.
   UpdatePlaybackPositionInternal(newCurrentTime);
 
   // Try to decode another frame to detect if we're at the end...
   DECODER_LOG("Seek completed, mCurrentPosition=%lld", mCurrentPosition.Ref());
@@ -2268,19 +2258,18 @@ nsresult MediaDecoderStateMachine::RunSt
   switch (mState) {
     case DECODER_STATE_SHUTDOWN:
     case DECODER_STATE_DORMANT:
     case DECODER_STATE_WAIT_FOR_CDM:
     case DECODER_STATE_DECODING_METADATA:
       return NS_OK;
 
     case DECODER_STATE_DECODING: {
-      if (IsDecodingFirstFrame()) {
-        // We haven't completed decoding our first frames, we can't start
-        // playback yet.
+      // Can't start playback until having decoded first frames.
+      if (!mSentFirstFrameLoadedEvent) {
         return NS_OK;
       }
       if (mPlayState != MediaDecoder::PLAY_STATE_PLAYING && IsPlaying())
       {
         // We're playing, but the element/decoder is in paused state. Stop
         // playing!
         StopPlayback();
       }
@@ -2487,17 +2476,17 @@ MediaDecoderStateMachine::UpdatePlayback
 }
 
 void MediaDecoderStateMachine::UpdateNextFrameStatus()
 {
   MOZ_ASSERT(OnTaskQueue());
 
   MediaDecoderOwner::NextFrameStatus status;
   const char* statusString;
-  if (mState <= DECODER_STATE_WAIT_FOR_CDM || IsDecodingFirstFrame()) {
+  if (mState < DECODER_STATE_DECODING || !mSentFirstFrameLoadedEvent) {
     status = MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE;
     statusString = "NEXT_FRAME_UNAVAILABLE";
   } else if (IsBuffering()) {
     status = MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_BUFFERING;
     statusString = "NEXT_FRAME_UNAVAILABLE_BUFFERING";
   } else if (IsSeeking()) {
     status = MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_SEEKING;
     statusString = "NEXT_FRAME_UNAVAILABLE_SEEKING";
@@ -2825,22 +2814,22 @@ MediaDecoderStateMachine::DumpDebugInfo(
   MOZ_ASSERT(NS_IsMainThread());
 
   // It is fine to capture a raw pointer here because MediaDecoder only call
   // this function before shutdown begins.
   nsCOMPtr<nsIRunnable> r = NS_NewRunnableFunction([this] () {
     mMediaSink->DumpDebugInfo();
     DUMP_LOG(
       "GetMediaTime=%lld GetClock=%lld mMediaSink=%p "
-      "mState=%s mPlayState=%d mDecodingFirstFrame=%d IsPlaying=%d "
+      "mState=%s mPlayState=%d mSentFirstFrameLoadedEvent=%d IsPlaying=%d "
       "mAudioStatus=%s mVideoStatus=%s mDecodedAudioEndTime=%lld mDecodedVideoEndTime=%lld "
       "mIsAudioPrerolling=%d mIsVideoPrerolling=%d "
       "mAudioCompleted=%d mVideoCompleted=%d",
       GetMediaTime(), mMediaSink->IsStarted() ? GetClock() : -1, mMediaSink.get(),
-      ToStateStr(), mPlayState.Ref(), mDecodingFirstFrame, IsPlaying(),
+      ToStateStr(), mPlayState.Ref(), mSentFirstFrameLoadedEvent, IsPlaying(),
       AudioRequestStatus(), VideoRequestStatus(), mDecodedAudioEndTime, mDecodedVideoEndTime,
       mIsAudioPrerolling, mIsVideoPrerolling, mAudioCompleted.Ref(), mVideoCompleted.Ref());
   });
 
   OwnerThread()->DispatchStateChange(r.forget());
 }
 
 void MediaDecoderStateMachine::AddOutputStream(ProcessedMediaStream* aStream,

--- a/dom/media/MediaDecoderStateMachine.h
+++ b/dom/media/MediaDecoderStateMachine.h
@@ -562,18 +562,17 @@ protected:
   void OnMetadataRead(MetadataHolder* aMetadata);
   void OnMetadataNotRead(ReadMetadataFailureReason aReason);
 
   // Checks whether we're finished decoding first audio and/or video packets.
   // If so will trigger firing loadeddata event.
   // If there are any queued seek, will change state to DECODER_STATE_SEEKING
   // and return true.
   bool MaybeFinishDecodeFirstFrame();
-  // Return true if we are currently decoding the first frames.
-  bool IsDecodingFirstFrame();
+
   void FinishDecodeFirstFrame();
 
   // Completes the seek operation, moves onto the next appropriate state.
   void SeekCompleted();
 
   // Queries our state to see whether the decode has finished for all streams.
   bool CheckIfDecodeComplete();
 
@@ -880,28 +879,24 @@ private:
 
   nsAutoPtr<MetadataTags> mMetadataTags;
 
   mozilla::MediaMetadataManager mMetadataManager;
 
   // Track our request to update the buffered ranges
   MozPromiseRequestHolder<MediaDecoderReader::BufferedUpdatePromise> mBufferedUpdateRequest;
 
-  // True if we need to call FinishDecodeFirstFrame() upon frame decoding
-  // succeeding.
-  bool mDecodingFirstFrame;
-
   // True if we are back from DECODER_STATE_DORMANT state and
   // LoadedMetadataEvent was already sent.
   bool mSentLoadedMetadataEvent;
-  // True if we are back from DECODER_STATE_DORMANT state and
-  // FirstFrameLoadedEvent was already sent, then we can skip
-  // SetStartTime because the mStartTime already set before. Also we don't need
-  // to decode any audio/video since the MediaDecoder will trigger a seek
-  // operation soon.
+
+  // True if we've decoded first frames (thus having the start time) and
+  // notified the FirstFrameLoaded event. Note we can't initiate seek until the
+  // start time is known which happens when the first frames are decoded or we
+  // are playing an MSE stream (the start time is always assumed 0).
   bool mSentFirstFrameLoadedEvent;
 
   bool mSentPlaybackEndedEvent;
 
   // True if video decoding is suspended.
   bool mVideoDecodeSuspended;
 
   // Track enabling video decode suspension via timer

--- a/dom/media/MediaFormatReader.cpp
+++ b/dom/media/MediaFormatReader.cpp
@@ -57,19 +57,19 @@ TrackTypeToStr(TrackInfo::TrackType aTra
   }
 }
 
 MediaFormatReader::MediaFormatReader(AbstractMediaDecoder* aDecoder,
                                      MediaDataDemuxer* aDemuxer,
                                      VideoFrameContainer* aVideoFrameContainer,
                                      layers::LayersBackend aLayersBackend)
   : MediaDecoderReader(aDecoder)
-  , mAudio(this, MediaData::AUDIO_DATA, Preferences::GetUint("media.audio-decode-ahead", 2),
+  , mAudio(this, MediaData::AUDIO_DATA,
            Preferences::GetUint("media.audio-max-decode-error", 3))
-  , mVideo(this, MediaData::VIDEO_DATA, Preferences::GetUint("media.video-decode-ahead", 2),
+  , mVideo(this, MediaData::VIDEO_DATA,
            Preferences::GetUint("media.video-max-decode-error", 2))
   , mDemuxer(aDemuxer)
   , mDemuxerInitDone(false)
   , mLastReportedNumDecodedFrames(0)
   , mPreviousDecodedKeyframeTime_us(sNoPreviousDecodedKeyframe)
   , mLayersBackendType(aLayersBackend)
   , mInitDone(false)
   , mIsEncrypted(false)
@@ -557,17 +557,17 @@ MediaFormatReader::RequestVideoData(bool
   if (!mVideo.HasInternalSeekPending() &&
       ShouldSkip(aSkipToNextKeyframe, timeThreshold)) {
     RefPtr<MediaDataPromise> p = mVideo.EnsurePromise(__func__);
     SkipVideoDemuxToNextKeyFrame(timeThreshold);
     return p;
   }
 
   RefPtr<MediaDataPromise> p = mVideo.EnsurePromise(__func__);
-  NotifyDecodingRequested(TrackInfo::kVideoTrack);
+  ScheduleUpdate(TrackInfo::kVideoTrack);
 
   return p;
 }
 
 void
 MediaFormatReader::OnDemuxFailed(TrackType aTrack, DemuxerFailureReason aFailure)
 {
   MOZ_ASSERT(OnTaskQueue());
@@ -601,17 +601,16 @@ MediaFormatReader::OnDemuxFailed(TrackTy
       MOZ_ASSERT(false);
       break;
   }
 }
 
 void
 MediaFormatReader::DoDemuxVideo()
 {
-  // TODO Use DecodeAhead value rather than 1.
   mVideo.mDemuxRequest.Begin(mVideo.mTrackDemuxer->GetSamples(1)
                       ->Then(OwnerThread(), __func__, this,
                              &MediaFormatReader::OnVideoDemuxCompleted,
                              &MediaFormatReader::OnVideoDemuxFailed));
 }
 
 void
 MediaFormatReader::OnVideoDemuxCompleted(RefPtr<MediaTrackDemuxer::SamplesHolder> aSamples)
@@ -652,25 +651,24 @@ MediaFormatReader::RequestAudioData()
   }
 
   if (mShutdown) {
     NS_WARNING("RequestAudioData on shutdown MediaFormatReader!");
     return MediaDataPromise::CreateAndReject(CANCELED, __func__);
   }
 
   RefPtr<MediaDataPromise> p = mAudio.EnsurePromise(__func__);
-  NotifyDecodingRequested(TrackInfo::kAudioTrack);
+  ScheduleUpdate(TrackInfo::kAudioTrack);
 
   return p;
 }
 
 void
 MediaFormatReader::DoDemuxAudio()
 {
-  // TODO Use DecodeAhead value rather than 1.
   mAudio.mDemuxRequest.Begin(mAudio.mTrackDemuxer->GetSamples(1)
                       ->Then(OwnerThread(), __func__, this,
                              &MediaFormatReader::OnAudioDemuxCompleted,
                              &MediaFormatReader::OnAudioDemuxFailed));
 }
 
 void
 MediaFormatReader::OnAudioDemuxCompleted(RefPtr<MediaTrackDemuxer::SamplesHolder> aSamples)
@@ -701,17 +699,17 @@ MediaFormatReader::NotifyNewOutput(Track
 }
 
 void
 MediaFormatReader::NotifyInputExhausted(TrackType aTrack)
 {
   MOZ_ASSERT(OnTaskQueue());
   LOGV("Decoder has requested more %s data", TrackTypeToStr(aTrack));
   auto& decoder = GetDecoderData(aTrack);
-  decoder.mInputExhausted = true;
+  decoder.mDecodePending = false;
   ScheduleUpdate(aTrack);
 }
 
 void
 MediaFormatReader::NotifyDrainComplete(TrackType aTrack)
 {
   MOZ_ASSERT(OnTaskQueue());
   auto& decoder = GetDecoderData(aTrack);
@@ -750,43 +748,31 @@ void
 MediaFormatReader::NotifyEndOfStream(TrackType aTrack)
 {
   MOZ_ASSERT(OnTaskQueue());
   auto& decoder = GetDecoderData(aTrack);
   decoder.mDemuxEOS = true;
   ScheduleUpdate(aTrack);
 }
 
-void
-MediaFormatReader::NotifyDecodingRequested(TrackType aTrack)
-{
-  MOZ_ASSERT(OnTaskQueue());
-  auto& decoder = GetDecoderData(aTrack);
-  decoder.mDecodingRequested = true;
-  ScheduleUpdate(aTrack);
-}
-
 bool
 MediaFormatReader::NeedInput(DecoderData& aDecoder)
 {
-  // We try to keep a few more compressed samples input than decoded samples
-  // have been output, provided the state machine has requested we send it a
-  // decoded sample. To account for H.264 streams which may require a longer
-  // run of input than we input, decoders fire an "input exhausted" callback,
-  // which overrides our "few more samples" threshold.
+  // To account for H.264 streams which may require a longer
+  // run of input than we input, decoders fire an "input exhausted" callback.
+  // The decoder will not be fed a new raw sample until InputExhausted
+  // has been called.
   return
+    (aDecoder.HasPromise() || aDecoder.mTimeThreshold.isSome()) &&
     !aDecoder.HasPendingDrain() &&
     !aDecoder.HasFatalError() &&
-    aDecoder.mDecodingRequested &&
     !aDecoder.mDemuxRequest.Exists() &&
+    !aDecoder.mOutput.Length() &&
     !aDecoder.HasInternalSeekPending() &&
-    aDecoder.mOutput.Length() <= aDecoder.mDecodeAhead &&
-    (aDecoder.mInputExhausted || !aDecoder.mQueuedSamples.IsEmpty() ||
-     aDecoder.mTimeThreshold.isSome() ||
-     aDecoder.mNumSamplesInput - aDecoder.mNumSamplesOutput <= aDecoder.mDecodeAhead);
+    !aDecoder.mDecodePending;
 }
 
 void
 MediaFormatReader::ScheduleUpdate(TrackType aTrack)
 {
   MOZ_ASSERT(OnTaskQueue());
   if (mShutdown) {
     return;
@@ -927,16 +913,17 @@ MediaFormatReader::DecodeDemuxedSamples(
                                         MediaRawData* aSample)
 {
   MOZ_ASSERT(OnTaskQueue());
   auto& decoder = GetDecoderData(aTrack);
   if (NS_FAILED(decoder.mDecoder->Input(aSample))) {
       LOG("Unable to pass frame to decoder");
       return false;
   }
+  decoder.mDecodePending = true;
   return true;
 }
 
 void
 MediaFormatReader::HandleDemuxedSamples(TrackType aTrack,
                                         AbstractMediaDecoder::AutoNotifyDecoded& aA)
 {
   MOZ_ASSERT(OnTaskQueue());
@@ -1002,17 +989,17 @@ MediaFormatReader::HandleDemuxedSamples(
       decoder.mLastStreamSourceID = info->GetID();
       decoder.mNextStreamSourceID.reset();
       // Reset will clear our array of queued samples. So make a copy now.
       nsTArray<RefPtr<MediaRawData>> samples{decoder.mQueuedSamples};
       Reset(aTrack);
       decoder.ShutdownDecoder();
       if (sample->mKeyframe) {
         decoder.mQueuedSamples.AppendElements(Move(samples));
-        NotifyDecodingRequested(aTrack);
+        ScheduleUpdate(aTrack);
       } else {
         TimeInterval time =
           TimeInterval(TimeUnit::FromMicroseconds(sample->mTime),
                        TimeUnit::FromMicroseconds(sample->GetEndTime()));
         InternalSeekTarget seekTarget =
           decoder.mTimeThreshold.refOr(InternalSeekTarget(time, false));
         LOG("Stream change occurred on a non-keyframe. Seeking to:%lld",
             sample->mTime);
@@ -1040,19 +1027,16 @@ MediaFormatReader::HandleDemuxedSamples(
     decoder.mQueuedSamples.RemoveElementAt(0);
     if (mDemuxOnly) {
       // If demuxed-only case, ReturnOutput will resolve with one demuxed data.
       // Then we should stop doing the iteration.
       return;
     }
     samplesPending = true;
   }
-
-  // We have serviced the decoder's request for more data.
-  decoder.mInputExhausted = false;
 }
 
 void
 MediaFormatReader::InternalSeek(TrackType aTrack, const InternalSeekTarget& aTarget)
 {
   MOZ_ASSERT(OnTaskQueue());
   LOG("%s internal seek to %f",
       TrackTypeToStr(aTrack), aTarget.Time().ToSeconds());
@@ -1066,17 +1050,17 @@ MediaFormatReader::InternalSeek(TrackTyp
              ->Then(OwnerThread(), __func__,
                     [self, aTrack] (media::TimeUnit aTime) {
                       auto& decoder = self->GetDecoderData(aTrack);
                       decoder.mSeekRequest.Complete();
                       MOZ_ASSERT(decoder.mTimeThreshold,
                                  "Seek promise must be disconnected when timethreshold is reset");
                       decoder.mTimeThreshold.ref().mHasSeeked = true;
                       self->SetVideoDecodeThreshold();
-                      self->NotifyDecodingRequested(aTrack);
+                      self->ScheduleUpdate(aTrack);
                     },
                     [self, aTrack] (DemuxerFailureReason aResult) {
                       auto& decoder = self->GetDecoderData(aTrack);
                       decoder.mSeekRequest.Complete();
                       switch (aResult) {
                         case DemuxerFailureReason::WAITING_FOR_DATA:
                           self->NotifyWaitingForData(aTrack);
                           break;
@@ -1270,16 +1254,17 @@ MediaFormatReader::Update(TrackType aTra
 
   if (decoder.mNeedDraining) {
     DrainDecoder(aTrack);
     return;
   }
 
   if (decoder.mError &&
       decoder.mError.ref() == MediaDataDecoderError::DECODE_ERROR) {
+    decoder.mDecodePending = false;
     decoder.mError.reset();
     if (++decoder.mNumOfConsecutiveError > decoder.mMaxConsecutiveError) {
       NotifyError(aTrack);
       return;
     }
     LOG("%s decoded error count %d", TrackTypeToStr(aTrack),
                                      decoder.mNumOfConsecutiveError);
     media::TimeUnit nextKeyframe;
@@ -1287,21 +1272,21 @@ MediaFormatReader::Update(TrackType aTra
         NS_SUCCEEDED(decoder.mTrackDemuxer->GetNextRandomAccessPoint(&nextKeyframe))) {
       SkipVideoDemuxToNextKeyFrame(decoder.mLastSampleTime.refOr(TimeInterval()).Length());
       return;
     }
   }
 
   bool needInput = NeedInput(decoder);
 
-  LOGV("Update(%s) ni=%d no=%d ie=%d, in:%llu out:%llu qs=%u pending:%u waiting:%d ahead:%d sid:%u",
-       TrackTypeToStr(aTrack), needInput, needOutput, decoder.mInputExhausted,
+  LOGV("Update(%s) ni=%d no=%d ie=%d, in:%llu out:%llu qs=%u pending:%u waiting:%d promise:%d sid:%u",
+       TrackTypeToStr(aTrack), needInput, needOutput, decoder.mDecodePending,
        decoder.mNumSamplesInput, decoder.mNumSamplesOutput,
        uint32_t(size_t(decoder.mSizeOfQueue)), uint32_t(decoder.mOutput.Length()),
-       decoder.mWaitingForData, !decoder.HasPromise(), decoder.mLastStreamSourceID);
+       decoder.mWaitingForData, decoder.HasPromise(), decoder.mLastStreamSourceID);
 
   if (decoder.mWaitingForData &&
       (!decoder.mTimeThreshold || decoder.mTimeThreshold.ref().mWaiting)) {
     // Nothing more we can do at present.
     LOGV("Still waiting for data.");
     return;
   }
 
@@ -1572,17 +1557,17 @@ void
 MediaFormatReader::OnVideoSkipCompleted(uint32_t aSkipped)
 {
   MOZ_ASSERT(OnTaskQueue());
   LOG("Skipping succeeded, skipped %u frames", aSkipped);
   mSkipRequest.Complete();
 
   VideoSkipReset(aSkipped);
 
-  NotifyDecodingRequested(TrackInfo::kVideoTrack);
+  ScheduleUpdate(TrackInfo::kVideoTrack);
 }
 
 void
 MediaFormatReader::OnVideoSkipFailed(MediaTrackDemuxer::SkipFailureHolder aFailure)
 {
   MOZ_ASSERT(OnTaskQueue());
   LOG("Skipping failed, skipped %u frames", aFailure.mSkipped);
   mSkipRequest.Complete();
@@ -1590,17 +1575,17 @@ MediaFormatReader::OnVideoSkipFailed(Med
   switch (aFailure.mFailure) {
     case DemuxerFailureReason::END_OF_STREAM: MOZ_FALLTHROUGH;
     case DemuxerFailureReason::WAITING_FOR_DATA:
       // Some frames may have been output by the decoder since we initiated the
       // videoskip process and we know they would be late.
       DropDecodedSamples(TrackInfo::kVideoTrack);
       // We can't complete the skip operation, will just service a video frame
       // normally.
-      NotifyDecodingRequested(TrackInfo::kVideoTrack);
+      ScheduleUpdate(TrackInfo::kVideoTrack);
       break;
     case DemuxerFailureReason::CANCELED: MOZ_FALLTHROUGH;
     case DemuxerFailureReason::SHUTDOWN:
       if (mVideo.HasPromise()) {
         mVideo.RejectPromise(CANCELED, __func__);
       }
       break;
     default:
@@ -2008,22 +1993,21 @@ MediaFormatReader::GetMozDebugReaderData
     MonitorAutoLock mon(mVideo.mMonitor);
     videoName = mVideo.mDescription;
   }
 
   result += nsPrintfCString("audio decoder: %s\n", audioName);
   result += nsPrintfCString("audio frames decoded: %lld\n",
                             mAudio.mNumSamplesOutputTotal);
   if (HasAudio()) {
-    result += nsPrintfCString("audio state: ni=%d no=%d ie=%d demuxr:%d demuxq:%d decoder:%d tt:%f tths:%d in:%llu out:%llu qs=%u pending:%u waiting:%d sid:%u\n",
+    result += nsPrintfCString("audio state: ni=%d no=%d ie=%d demuxr:%d demuxq:%d tt:%f tths:%d in:%llu out:%llu qs=%u pending:%u waiting:%d sid:%u\n",
                               NeedInput(mAudio), mAudio.HasPromise(),
-                              mAudio.mInputExhausted,
+                              mAudio.mDecodePending,
                               mAudio.mDemuxRequest.Exists(),
                               int(mAudio.mQueuedSamples.Length()),
-                              mAudio.mDecodingRequested,
                               mAudio.mTimeThreshold
                               ? mAudio.mTimeThreshold.ref().Time().ToSeconds()
                               : -1.0,
                               mAudio.mTimeThreshold
                               ? mAudio.mTimeThreshold.ref().mHasSeeked
                               : -1,
                               mAudio.mNumSamplesInput, mAudio.mNumSamplesOutput,
                               unsigned(size_t(mAudio.mSizeOfQueue)),
@@ -2032,22 +2016,21 @@ MediaFormatReader::GetMozDebugReaderData
   }
   result += nsPrintfCString("video decoder: %s\n", videoName);
   result += nsPrintfCString("hardware video decoding: %s\n",
                             VideoIsHardwareAccelerated() ? "enabled" : "disabled");
   result += nsPrintfCString("video frames decoded: %lld (skipped:%lld)\n",
                             mVideo.mNumSamplesOutputTotal,
                             mVideo.mNumSamplesSkippedTotal);
   if (HasVideo()) {
-    result += nsPrintfCString("video state: ni=%d no=%d ie=%d demuxr:%d demuxq:%d decoder:%d tt:%f tths:%d in:%llu out:%llu qs=%u pending:%u waiting:%d sid:%u\n",
+    result += nsPrintfCString("video state: ni=%d no=%d ie=%d demuxr:%d demuxq:%d tt:%f tths:%d in:%llu out:%llu qs=%u pending:%u waiting:%d sid:%u\n",
                               NeedInput(mVideo), mVideo.HasPromise(),
-                              mVideo.mInputExhausted,
+                              mVideo.mDecodePending,
                               mVideo.mDemuxRequest.Exists(),
                               int(mVideo.mQueuedSamples.Length()),
-                              mVideo.mDecodingRequested,
                               mVideo.mTimeThreshold
                               ? mVideo.mTimeThreshold.ref().Time().ToSeconds()
                               : -1.0,
                               mVideo.mTimeThreshold
                               ? mVideo.mTimeThreshold.ref().mHasSeeked
                               : -1,
                               mVideo.mNumSamplesInput, mVideo.mNumSamplesOutput,
                               unsigned(size_t(mVideo.mSizeOfQueue)),
@@ -2075,14 +2058,14 @@ MediaFormatReader::SetBlankDecode(TrackT
 
   if (decoder.mIsBlankDecode == aIsBlankDecode) {
     return;
   }
 
   decoder.mIsBlankDecode = aIsBlankDecode;
   decoder.Flush();
   decoder.ShutdownDecoder();
-  NotifyDecodingRequested(TrackInfo::kVideoTrack); // Calls ScheduleUpdate().
+  ScheduleUpdate(TrackInfo::kVideoTrack);
 
   return;
 }
 
 } // namespace mozilla

--- a/dom/media/MediaFormatReader.h
+++ b/dom/media/MediaFormatReader.h
@@ -164,17 +164,16 @@ private:
   // Drain the current decoder.
   void DrainDecoder(TrackType aTrack);
   void NotifyNewOutput(TrackType aTrack, MediaData* aSample);
   void NotifyInputExhausted(TrackType aTrack);
   void NotifyDrainComplete(TrackType aTrack);
   void NotifyError(TrackType aTrack, MediaDataDecoderError aError = MediaDataDecoderError::FATAL_ERROR);
   void NotifyWaitingForData(TrackType aTrack);
   void NotifyEndOfStream(TrackType aTrack);
-  void NotifyDecodingRequested(TrackType aTrack);
 
   void ExtractCryptoInitData(nsTArray<uint8_t>& aInitData);
 
   // Initializes mLayersBackendType if possible.
   void InitLayersBackendType();
 
   // DecoderCallback proxies the MediaDataDecoderCallback calls to these
   // functions.
@@ -226,31 +225,28 @@ private:
   private:
     MediaFormatReader* mReader;
     TrackType mType;
   };
 
   struct DecoderData {
     DecoderData(MediaFormatReader* aOwner,
                 MediaData::Type aType,
-                uint32_t aDecodeAhead,
                 uint32_t aNumOfMaxError)
       : mOwner(aOwner)
       , mType(aType)
       , mMonitor("DecoderData")
       , mDescription("shutdown")
-      , mDecodeAhead(aDecodeAhead)
       , mUpdateScheduled(false)
       , mDemuxEOS(false)
       , mWaitingForData(false)
       , mReceivedNewData(false)
       , mDecoderInitialized(false)
-      , mDecodingRequested(false)
       , mOutputRequested(false)
-      , mInputExhausted(false)
+      , mDecodePending(false)
       , mNeedDraining(false)
       , mDraining(false)
       , mDrainComplete(false)
       , mNumOfConsecutiveError(0)
       , mMaxConsecutiveError(aNumOfMaxError)
       , mNumSamplesInput(0)
       , mNumSamplesOutput(0)
       , mNumSamplesOutputTotal(0)
@@ -283,17 +279,16 @@ private:
       if (mDecoder) {
         mDecoder->Shutdown();
       }
       mDescription = "shutdown";
       mDecoder = nullptr;
     }
 
     // Only accessed from reader's task queue.
-    uint32_t mDecodeAhead;
     bool mUpdateScheduled;
     bool mDemuxEOS;
     bool mWaitingForData;
     bool mReceivedNewData;
 
     // Pending seek.
     MozPromiseRequestHolder<MediaTrackDemuxer::SeekPromise> mSeekRequest;
 
@@ -307,21 +302,24 @@ private:
       return !mWaitingPromise.IsEmpty();
     }
 
     // MediaDataDecoder handler's variables.
     // Decoder initialization promise holder.
     MozPromiseRequestHolder<MediaDataDecoder::InitPromise> mInitPromise;
     // False when decoder is created. True when decoder Init() promise is resolved.
     bool mDecoderInitialized;
-    // Set when decoding can proceed. It is reset when a decoding promise is
-    // rejected or prior a seek operation.
-    bool mDecodingRequested;
     bool mOutputRequested;
-    bool mInputExhausted;
+    // Set to true once the MediaDataDecoder has been fed a compressed sample.
+    // No more sample will be passed to the decoder while true.
+    // mDecodePending is reset when:
+    // 1- The decoder returns a sample
+    // 2- The decoder calls InputExhausted
+    // 3- The decoder is Flushed or Reset.
+    bool mDecodePending;
     bool mNeedDraining;
     bool mDraining;
     bool mDrainComplete;
 
     bool HasPendingDrain() const
     {
       return mDraining || mDrainComplete;
     }
@@ -371,19 +369,18 @@ private:
     // Flush the decoder if present and reset decoding related data.
     // Decoding will be suspended until mInputRequested is set again.
     // Following a flush, the decoder is ready to accept any new data.
     void Flush()
     {
       if (mDecoder) {
         mDecoder->Flush();
       }
-      mDecodingRequested = false;
       mOutputRequested = false;
-      mInputExhausted = false;
+      mDecodePending = false;
       mOutput.Clear();
       mNumSamplesInput = 0;
       mNumSamplesOutput = 0;
       mSizeOfQueue = 0;
       mDraining = false;
       mDrainComplete = false;
     }
 
@@ -392,20 +389,19 @@ private:
     // Decoding will be suspended until mInputRequested is set again.
     // The track demuxer is *not* reset.
     void ResetState()
     {
       MOZ_ASSERT(mOwner->OnTaskQueue());
       mDemuxEOS = false;
       mWaitingForData = false;
       mQueuedSamples.Clear();
-      mDecodingRequested = false;
       mOutputRequested = false;
-      mInputExhausted = false;
       mNeedDraining = false;
+      mDecodePending = false;
       mDraining = false;
       mDrainComplete = false;
       mTimeThreshold.reset();
       mLastSampleTime.reset();
       mOutput.Clear();
       mNumSamplesInput = 0;
       mNumSamplesOutput = 0;
       mSizeOfQueue = 0;
@@ -436,19 +432,18 @@ private:
     bool mIsBlankDecode;
 
   };
 
   class DecoderDataWithPromise : public DecoderData {
   public:
     DecoderDataWithPromise(MediaFormatReader* aOwner,
                            MediaData::Type aType,
-                           uint32_t aDecodeAhead,
                            uint32_t aNumOfMaxError)
-      : DecoderData(aOwner, aType, aDecodeAhead, aNumOfMaxError)
+      : DecoderData(aOwner, aType, aNumOfMaxError)
       , mHasPromise(false)
 
     {}
 
     bool HasPromise() const override
     {
       return mHasPromise;
     }
@@ -467,17 +462,16 @@ private:
       mHasPromise = false;
     }
 
     void RejectPromise(MediaDecoderReader::NotDecodedReason aReason,
                        const char* aMethodName) override
     {
       MOZ_ASSERT(mOwner->OnTaskQueue());
       mPromise.Reject(aReason, aMethodName);
-      mDecodingRequested = false;
       mHasPromise = false;
     }
 
   private:
     MozPromiseHolder<MediaDataPromise> mPromise;
     Atomic<bool> mHasPromise;
   };
 

--- a/dom/media/MediaStreamGraph.cpp
+++ b/dom/media/MediaStreamGraph.cpp
@@ -1072,16 +1072,35 @@ void
 MediaStreamGraph::NotifyOutputData(AudioDataValue* aBuffer, size_t aFrames,
                                    TrackRate aRate, uint32_t aChannels)
 {
   for (auto& listener : mAudioInputs) {
     listener->NotifyOutputData(this, aBuffer, aFrames, aRate, aChannels);
   }
 }
 
+void
+MediaStreamGraph::AssertOnGraphThreadOrNotRunning() const
+{
+  // either we're on the right thread (and calling CurrentDriver() is safe),
+  // or we're going to assert anyways, so don't cross-check CurrentDriver
+#ifdef DEBUG
+  MediaStreamGraphImpl const * graph =
+    static_cast<MediaStreamGraphImpl const *>(this);
+  // if all the safety checks fail, assert we own the monitor
+  if (!graph->mDriver->OnThread()) {
+    if (!(graph->mDetectedNotRunning &&
+          graph->mLifecycleState > MediaStreamGraphImpl::LIFECYCLE_RUNNING &&
+          NS_IsMainThread())) {
+      graph->mMonitor.AssertCurrentThreadOwns();
+    }
+  }
+#endif
+}
+
 bool
 MediaStreamGraphImpl::ShouldUpdateMainThread()
 {
   if (mRealtime) {
     return true;
   }
 
   TimeStamp now = TimeStamp::Now();

--- a/dom/media/MediaStreamGraph.h
+++ b/dom/media/MediaStreamGraph.h
@@ -1348,16 +1348,17 @@ public:
    * Media graph thread only.
    * Dispatches a runnable that will run on the main thread after all
    * main-thread stream state has been next updated.
    * Should only be called during MediaStreamListener callbacks or during
    * ProcessedMediaStream::ProcessInput().
    */
   virtual void DispatchToMainThreadAfterStreamStateUpdate(already_AddRefed<nsIRunnable> aRunnable)
   {
+    AssertOnGraphThreadOrNotRunning();
     *mPendingUpdateRunnables.AppendElement() = aRunnable;
   }
 
   /**
    * Returns graph sample rate in Hz.
    */
   TrackRate GraphRate() const { return mSampleRate; }
 
@@ -1369,16 +1370,18 @@ public:
 
   /**
    * Data going to the speakers from the GraphDriver's DataCallback
    * to notify any listeners (for echo cancellation).
    */
   void NotifyOutputData(AudioDataValue* aBuffer, size_t aFrames,
                         TrackRate aRate, uint32_t aChannels);
 
+  void AssertOnGraphThreadOrNotRunning() const;
+
 protected:
   explicit MediaStreamGraph(TrackRate aSampleRate)
     : mSampleRate(aSampleRate)
   {
     MOZ_COUNT_CTOR(MediaStreamGraph);
   }
   virtual ~MediaStreamGraph()
   {

--- a/dom/media/MediaStreamGraphImpl.h
+++ b/dom/media/MediaStreamGraphImpl.h
@@ -197,34 +197,18 @@ public:
   /**
    * Respond to CollectReports with sizes collected on the graph thread.
    */
   static void
   FinishCollectReports(nsIHandleReportCallback* aHandleReport,
                        nsISupports* aData,
                        const nsTArray<AudioNodeSizes>& aAudioStreamSizes);
 
-  // The following methods run on the graph thread (or possibly the main thread if
-  // mLifecycleState > LIFECYCLE_RUNNING)
-  void AssertOnGraphThreadOrNotRunning() const
-  {
-    // either we're on the right thread (and calling CurrentDriver() is safe),
-    // or we're going to assert anyways, so don't cross-check CurrentDriver
-#ifdef DEBUG
-    // if all the safety checks fail, assert we own the monitor
-    if (!mDriver->OnThread()) {
-      if (!(mDetectedNotRunning &&
-            mLifecycleState > LIFECYCLE_RUNNING &&
-            NS_IsMainThread())) {
-        mMonitor.AssertCurrentThreadOwns();
-      }
-    }
-#endif
-  }
-
+  // The following methods run on the graph thread (or possibly the main thread
+  // if mLifecycleState > LIFECYCLE_RUNNING)
   void CollectSizesForMemoryReport(
          already_AddRefed<nsIHandleReportCallback> aHandleReport,
          already_AddRefed<nsISupports> aHandlerData);
 
   /**
    * Returns true if this MediaStreamGraph should keep running
    */
   bool UpdateMainThreadState();

--- a/dom/media/flac/FlacFrameParser.cpp
+++ b/dom/media/flac/FlacFrameParser.cpp
@@ -127,17 +127,17 @@ FlacFrameParser::DecodeHeaderBlock(const
       uint32_t sampleRate = (blob >> 44) & BITMASK(20);
       if (!sampleRate) {
         return false;
       }
       uint32_t numChannels = ((blob >> 41) & BITMASK(3)) + 1;
       if (numChannels > FLAC_MAX_CHANNELS) {
         return false;
       }
-      uint32_t bps = ((blob >> 38) & BITMASK(5)) + 1;
+      uint32_t bps = ((blob >> 36) & BITMASK(5)) + 1;
       if (bps > 24) {
         return false;
       }
       mNumFrames = blob & BITMASK(36);
 
       mInfo.mMimeType = "audio/flac";
       mInfo.mRate = sampleRate;
       mInfo.mChannels = numChannels;

--- a/dom/media/platforms/PlatformDecoderModule.h
+++ b/dom/media/platforms/PlatformDecoderModule.h
@@ -170,16 +170,19 @@ public:
   virtual void Output(MediaData* aData) = 0;
 
   // Denotes an error in the decoding process. The reader will stop calling
   // the decoder.
   virtual void Error(MediaDataDecoderError aError) = 0;
 
   // Denotes that the last input sample has been inserted into the decoder,
   // and no more output can be produced unless more input is sent.
+  // A frame decoding session is completed once InputExhausted has been called.
+  // MediaDataDecoder::Input will not be called again until InputExhausted has
+  // been called.
   virtual void InputExhausted() = 0;
 
   virtual void DrainComplete() = 0;
 
   virtual void ReleaseMediaResources() {}
 
   virtual bool OnReaderTaskQueue() = 0;
 

--- a/dom/media/platforms/agnostic/BlankDecoderModule.cpp
+++ b/dom/media/platforms/agnostic/BlankDecoderModule.cpp
@@ -91,21 +91,17 @@ private:
     }
 
     // Frames come out in DTS order but we need to output them in PTS order.
     mReorderQueue.Push(aData);
 
     while (mReorderQueue.Length() > mMaxRefFrames) {
       mCallback->Output(mReorderQueue.Pop().get());
     }
-
-    if (mReorderQueue.Length() <= mMaxRefFrames) {
-      mCallback->InputExhausted();
-    }
-
+    mCallback->InputExhausted();
   }
 
 private:
   nsAutoPtr<BlankMediaDataCreator> mCreator;
   MediaDataDecoderCallback* mCallback;
   const uint32_t mMaxRefFrames;
   ReorderQueue mReorderQueue;
   TrackInfo::TrackType mType;

--- a/dom/media/platforms/agnostic/OpusDecoder.cpp
+++ b/dom/media/platforms/agnostic/OpusDecoder.cpp
@@ -158,22 +158,19 @@ OpusDataDecoder::ProcessDecode(MediaRawD
   switch (err) {
     case DecodeError::FATAL_ERROR:
       mCallback->Error(MediaDataDecoderError::FATAL_ERROR);
       return;
     case DecodeError::DECODE_ERROR:
       mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
       break;
     case DecodeError::DECODE_SUCCESS:
+      mCallback->InputExhausted();
       break;
   }
-
-  if (mTaskQueue->IsEmpty()) {
-    mCallback->InputExhausted();
-  }
 }
 
 OpusDataDecoder::DecodeError
 OpusDataDecoder::DoDecode(MediaRawData* aSample)
 {
   int64_t aDiscardPadding = 0;
   if (aSample->mExtraData) {
     aDiscardPadding = BigEndian::readInt64(aSample->mExtraData->Elements());

--- a/dom/media/platforms/agnostic/TheoraDecoder.cpp
+++ b/dom/media/platforms/agnostic/TheoraDecoder.cpp
@@ -197,17 +197,17 @@ void
 TheoraDecoder::ProcessDecode(MediaRawData* aSample)
 {
   MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());
   if (mIsFlushing) {
     return;
   }
   if (DoDecode(aSample) == -1) {
     mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
-  } else if (mTaskQueue->IsEmpty()) {
+  } else {
     mCallback->InputExhausted();
   }
 }
 
 nsresult
 TheoraDecoder::Input(MediaRawData* aSample)
 {
   MOZ_ASSERT(mCallback->OnReaderTaskQueue());

--- a/dom/media/platforms/agnostic/VPXDecoder.cpp
+++ b/dom/media/platforms/agnostic/VPXDecoder.cpp
@@ -187,17 +187,17 @@ void
 VPXDecoder::ProcessDecode(MediaRawData* aSample)
 {
   MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());
   if (mIsFlushing) {
     return;
   }
   if (DoDecode(aSample) == -1) {
     mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
-  } else if (mTaskQueue->IsEmpty()) {
+  } else {
     mCallback->InputExhausted();
   }
 }
 
 nsresult
 VPXDecoder::Input(MediaRawData* aSample)
 {
   MOZ_ASSERT(mCallback->OnReaderTaskQueue());

--- a/dom/media/platforms/agnostic/VorbisDecoder.cpp
+++ b/dom/media/platforms/agnostic/VorbisDecoder.cpp
@@ -138,17 +138,17 @@ void
 VorbisDataDecoder::ProcessDecode(MediaRawData* aSample)
 {
   MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());
   if (mIsFlushing) {
     return;
   }
   if (DoDecode(aSample) == -1) {
     mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
-  } else if (mTaskQueue->IsEmpty()) {
+  } else {
     mCallback->InputExhausted();
   }
 }
 
 int
 VorbisDataDecoder::DoDecode(MediaRawData* aSample)
 {
   MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());

--- a/dom/media/platforms/agnostic/WAVDecoder.cpp
+++ b/dom/media/platforms/agnostic/WAVDecoder.cpp
@@ -63,16 +63,18 @@ WaveDataDecoder::Init()
   return InitPromise::CreateAndResolve(TrackInfo::kAudioTrack, __func__);
 }
 
 nsresult
 WaveDataDecoder::Input(MediaRawData* aSample)
 {
   if (!DoDecode(aSample)) {
     mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
+  } else {
+    mCallback->InputExhausted();
   }
   return NS_OK;
 }
 
 bool
 WaveDataDecoder::DoDecode(MediaRawData* aSample)
 {
   size_t aLength = aSample->Size();

--- a/dom/media/platforms/apple/AppleATDecoder.cpp
+++ b/dom/media/platforms/apple/AppleATDecoder.cpp
@@ -210,20 +210,17 @@ AppleATDecoder::SubmitSample(MediaRawDat
       if (NS_FAILED(DecodeSample(mQueuedSamples[i]))) {
         mQueuedSamples.Clear();
         mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
         return;
       }
     }
     mQueuedSamples.Clear();
   }
-
-  if (mTaskQueue->IsEmpty()) {
-    mCallback->InputExhausted();
-  }
+  mCallback->InputExhausted();
 }
 
 nsresult
 AppleATDecoder::DecodeSample(MediaRawData* aSample)
 {
   MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());
 
   // Array containing the queued decoded audio frames, about to be output.

--- a/dom/media/platforms/apple/AppleVTDecoder.cpp
+++ b/dom/media/platforms/apple/AppleVTDecoder.cpp
@@ -29,21 +29,19 @@ AppleVTDecoder::AppleVTDecoder(const Vid
                                MediaDataDecoderCallback* aCallback,
                                layers::ImageContainer* aImageContainer)
   : mExtraData(aConfig.mExtraData)
   , mCallback(aCallback)
   , mPictureWidth(aConfig.mImage.width)
   , mPictureHeight(aConfig.mImage.height)
   , mDisplayWidth(aConfig.mDisplay.width)
   , mDisplayHeight(aConfig.mDisplay.height)
-  , mQueuedSamples(0)
   , mTaskQueue(aTaskQueue)
   , mMaxRefFrames(mp4_demuxer::H264::ComputeMaxRefFrames(aConfig.mExtraData))
   , mImageContainer(aImageContainer)
-  , mInputIncoming(0)
   , mIsShutDown(false)
 #ifdef MOZ_WIDGET_UIKIT
   , mUseSoftwareImages(true)
 #else
   , mUseSoftwareImages(false)
 #endif
   , mIsFlushing(false)
   , mMonitor("AppleVideoDecoder")
@@ -83,34 +81,30 @@ AppleVTDecoder::Input(MediaRawData* aSam
 
   LOG("mp4 input sample %p pts %lld duration %lld us%s %d bytes",
       aSample,
       aSample->mTime,
       aSample->mDuration,
       aSample->mKeyframe ? " keyframe" : "",
       aSample->Size());
 
-  mInputIncoming++;
-
   mTaskQueue->Dispatch(NewRunnableMethod<RefPtr<MediaRawData>>(
     this, &AppleVTDecoder::ProcessDecode, aSample));
   return NS_OK;
 }
 
 nsresult
 AppleVTDecoder::Flush()
 {
   MOZ_ASSERT(mCallback->OnReaderTaskQueue());
   mIsFlushing = true;
   nsCOMPtr<nsIRunnable> runnable =
     NewRunnableMethod(this, &AppleVTDecoder::ProcessFlush);
   SyncRunnable::DispatchToThread(mTaskQueue, runnable);
   mIsFlushing = false;
-  // All ProcessDecode() tasks should be done.
-  MOZ_ASSERT(mInputIncoming == 0);
 
   mSeekTargetThreshold.reset();
 
   return NS_OK;
 }
 
 nsresult
 AppleVTDecoder::Drain()
@@ -137,28 +131,21 @@ AppleVTDecoder::Shutdown()
   return NS_OK;
 }
 
 nsresult
 AppleVTDecoder::ProcessDecode(MediaRawData* aSample)
 {
   AssertOnTaskQueueThread();
 
-  mInputIncoming--;
-
   if (mIsFlushing) {
     return NS_OK;
   }
 
   auto rv = DoDecode(aSample);
-  // Ask for more data.
-  if (NS_SUCCEEDED(rv) && !mInputIncoming && mQueuedSamples <= mMaxRefFrames) {
-    LOG("%s task queue empty; requesting more data", GetDescriptionName());
-    mCallback->InputExhausted();
-  }
 
   return rv;
 }
 
 void
 AppleVTDecoder::ProcessShutdown()
 {
   if (mSession) {
@@ -208,27 +195,25 @@ AppleVTDecoder::CreateAppleFrameRef(cons
 
 void
 AppleVTDecoder::DrainReorderedFrames()
 {
   MonitorAutoLock mon(mMonitor);
   while (!mReorderQueue.IsEmpty()) {
     mCallback->Output(mReorderQueue.Pop().get());
   }
-  mQueuedSamples = 0;
 }
 
 void
 AppleVTDecoder::ClearReorderedFrames()
 {
   MonitorAutoLock mon(mMonitor);
   while (!mReorderQueue.IsEmpty()) {
     mReorderQueue.Pop();
   }
-  mQueuedSamples = 0;
 }
 
 void
 AppleVTDecoder::SetSeekThreshold(const media::TimeUnit& aTime)
 {
   LOG("SetSeekThreshold %lld", aTime.ToMicroseconds());
   mSeekTargetThreshold = Some(aTime);
 }
@@ -283,26 +268,20 @@ AppleVTDecoder::OutputFrame(CVPixelBuffe
   LOG("mp4 output frame %lld dts %lld pts %lld duration %lld us%s",
       aFrameRef.byte_offset,
       aFrameRef.decode_timestamp.ToMicroseconds(),
       aFrameRef.composition_timestamp.ToMicroseconds(),
       aFrameRef.duration.ToMicroseconds(),
       aFrameRef.is_sync_point ? " keyframe" : ""
   );
 
-  if (mQueuedSamples > mMaxRefFrames) {
-    // We had stopped requesting more input because we had received too much at
-    // the time. We can ask for more once again.
+  if (!aImage) {
+    // Image was dropped by decoder or none return yet.
+    // We need more input to continue.
     mCallback->InputExhausted();
-  }
-  MOZ_ASSERT(mQueuedSamples);
-  mQueuedSamples--;
-
-  if (!aImage) {
-    // Image was dropped by decoder.
     return NS_OK;
   }
 
   bool useNullSample = false;
   if (mSeekTargetThreshold.isSome()) {
     if ((aFrameRef.composition_timestamp + aFrameRef.duration) < mSeekTargetThreshold.ref()) {
       useNullSample = true;
     } else {
@@ -405,19 +384,20 @@ AppleVTDecoder::OutputFrame(CVPixelBuffe
     mCallback->Error(MediaDataDecoderError::FATAL_ERROR);
     return NS_ERROR_FAILURE;
   }
 
   // Frames come out in DTS order but we need to output them
   // in composition order.
   MonitorAutoLock mon(mMonitor);
   mReorderQueue.Push(data);
-  while (mReorderQueue.Length() > mMaxRefFrames) {
+  if (mReorderQueue.Length() > mMaxRefFrames) {
     mCallback->Output(mReorderQueue.Pop().get());
   }
+  mCallback->InputExhausted();
   LOG("%llu decoded frames queued",
       static_cast<unsigned long long>(mReorderQueue.Length()));
 
   return NS_OK;
 }
 
 nsresult
 AppleVTDecoder::WaitForAsynchronousFrames()
@@ -475,18 +455,16 @@ AppleVTDecoder::DoDecode(MediaRawData* a
   }
   CMSampleTimingInfo timestamp = TimingInfoFromSample(aSample);
   rv = CMSampleBufferCreate(kCFAllocatorDefault, block, true, 0, 0, mFormat, 1, 1, &timestamp, 0, NULL, sample.receive());
   if (rv != noErr) {
     NS_ERROR("Couldn't create CMSampleBuffer");
     return NS_ERROR_FAILURE;
   }
 
-  mQueuedSamples++;
-
   VTDecodeFrameFlags decodeFlags =
     kVTDecodeFrame_EnableAsynchronousDecompression;
   rv = VTDecompressionSessionDecodeFrame(mSession,
                                          sample,
                                          decodeFlags,
                                          CreateAppleFrameRef(aSample),
                                          &infoFlags);
   if (rv != noErr && !(infoFlags & kVTDecodeInfo_FrameDropped)) {

--- a/dom/media/platforms/apple/AppleVTDecoder.h
+++ b/dom/media/platforms/apple/AppleVTDecoder.h
@@ -85,35 +85,27 @@ private:
 
   const RefPtr<MediaByteBuffer> mExtraData;
   MediaDataDecoderCallback* mCallback;
   const uint32_t mPictureWidth;
   const uint32_t mPictureHeight;
   const uint32_t mDisplayWidth;
   const uint32_t mDisplayHeight;
 
-  // Number of times a sample was queued via Input(). Will be decreased upon
-  // the decoder's callback being invoked.
-  // This is used to calculate how many frames has been buffered by the decoder.
-  Atomic<uint32_t> mQueuedSamples;
-
   // Method to set up the decompression session.
   nsresult InitializeSession();
   nsresult WaitForAsynchronousFrames();
   CFDictionaryRef CreateDecoderSpecification();
   CFDictionaryRef CreateDecoderExtensions();
   // Method to pass a frame to VideoToolbox for decoding.
   nsresult DoDecode(MediaRawData* aSample);
 
   const RefPtr<TaskQueue> mTaskQueue;
   const uint32_t mMaxRefFrames;
   const RefPtr<layers::ImageContainer> mImageContainer;
-  // Increased when Input is called, and decreased when ProcessFrame runs.
-  // Reaching 0 indicates that there's no pending Input.
-  Atomic<uint32_t> mInputIncoming;
   Atomic<bool> mIsShutDown;
   const bool mUseSoftwareImages;
 
   // Set on reader/decode thread calling Flush() to indicate that output is
   // not required and so input samples on mTaskQueue need not be processed.
   // Cleared on mTaskQueue in ProcessDrain().
   Atomic<bool> mIsFlushing;
   // Protects mReorderQueue.

--- a/dom/media/platforms/ffmpeg/FFmpegAudioDecoder.cpp
+++ b/dom/media/platforms/ffmpeg/FFmpegAudioDecoder.cpp
@@ -128,16 +128,17 @@ FFmpegAudioDecoder<LIBAV_VER>::DoDecode(
 
   if (!PrepareFrame()) {
     NS_WARNING("FFmpeg audio decoder failed to allocate frame.");
     return DecodeResult::FATAL_ERROR;
   }
 
   int64_t samplePosition = aSample->mOffset;
   media::TimeUnit pts = media::TimeUnit::FromMicroseconds(aSample->mTime);
+  bool didOutput = false;
 
   while (packet.size > 0) {
     int decoded;
     int bytesConsumed =
       mLib->avcodec_decode_audio4(mCodecContext, mFrame, &decoded, &packet);
 
     if (bytesConsumed < 0) {
       NS_WARNING("FFmpeg audio decoder error.");
@@ -176,28 +177,29 @@ FFmpegAudioDecoder<LIBAV_VER>::DoDecode(
       RefPtr<AudioData> data = new AudioData(samplePosition,
                                              pts.ToMicroseconds(),
                                              duration.ToMicroseconds(),
                                              mFrame->nb_samples,
                                              Move(audio),
                                              numChannels,
                                              samplingRate);
       mCallback->Output(data);
+      didOutput = true;
       pts += duration;
       if (!pts.IsValid()) {
         NS_WARNING("Invalid count of accumulated audio samples");
         return DecodeResult::DECODE_ERROR;
       }
     }
     packet.data += bytesConsumed;
     packet.size -= bytesConsumed;
     samplePosition += bytesConsumed;
   }
 
-  return DecodeResult::DECODE_FRAME;
+  return didOutput ? DecodeResult::DECODE_FRAME : DecodeResult::DECODE_NO_FRAME;
 }
 
 void
 FFmpegAudioDecoder<LIBAV_VER>::ProcessDrain()
 {
   ProcessFlush();
   mCallback->DrainComplete();
 }

--- a/dom/media/platforms/ffmpeg/FFmpegDataDecoder.cpp
+++ b/dom/media/platforms/ffmpeg/FFmpegDataDecoder.cpp
@@ -112,20 +112,22 @@ FFmpegDataDecoder<LIBAV_VER>::ProcessDec
   }
   switch (DoDecode(aSample)) {
     case DecodeResult::DECODE_ERROR:
       mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
       break;
     case DecodeResult::FATAL_ERROR:
       mCallback->Error(MediaDataDecoderError::FATAL_ERROR);
       break;
+    case DecodeResult::DECODE_NO_FRAME:
+    case DecodeResult::DECODE_FRAME:
+      mCallback->InputExhausted();
+      break;
     default:
-      if (mTaskQueue->IsEmpty()) {
-        mCallback->InputExhausted();
-      }
+      break;
   }
 }
 
 nsresult
 FFmpegDataDecoder<LIBAV_VER>::Input(MediaRawData* aSample)
 {
   mTaskQueue->Dispatch(NewRunnableMethod<RefPtr<MediaRawData>>(
     this, &FFmpegDataDecoder::ProcessDecode, aSample));

--- a/dom/media/platforms/wmf/WMFMediaDataDecoder.cpp
+++ b/dom/media/platforms/wmf/WMFMediaDataDecoder.cpp
@@ -144,19 +144,17 @@ WMFMediaDataDecoder::ProcessOutput()
   RefPtr<MediaData> output;
   HRESULT hr = S_OK;
   while (SUCCEEDED(hr = mMFTManager->Output(mLastStreamOffset, output)) &&
          output) {
     mHasSuccessfulOutput = true;
     mCallback->Output(output);
   }
   if (hr == MF_E_TRANSFORM_NEED_MORE_INPUT) {
-    if (mTaskQueue->IsEmpty()) {
-      mCallback->InputExhausted();
-    }
+    mCallback->InputExhausted();
   } else if (FAILED(hr)) {
     NS_WARNING("WMFMediaDataDecoder failed to output data");
     mCallback->Error(MediaDataDecoderError::DECODE_ERROR);
     if (!mRecordedError) {
       SendTelemetry(hr);
       mRecordedError = true;
     }
   }

--- a/dom/media/test/external/external_media_tests/media_utils/youtube_puppeteer.py
+++ b/dom/media/test/external/external_media_tests/media_utils/youtube_puppeteer.py
@@ -10,19 +10,26 @@ from marionette import Marionette
 from marionette_driver import By, expected, Wait
 from marionette_driver.errors import TimeoutException, NoSuchElementException
 from video_puppeteer import VideoPuppeteer, VideoException
 from external_media_tests.utils import verbose_until
 
 
 class YouTubePuppeteer(VideoPuppeteer):
     """
-    Wrapper around a YouTube #movie_player element.
+    Wrapper around a YouTube .html5-video-player element.
 
-    Partial reference: https://developers.google.com/youtube/js_api_reference.
+    Can be used with youtube videos or youtube videos at embedded URLS. E.g.
+    both https://www.youtube.com/watch?v=AbAACm1IQE0 and
+    https://www.youtube.com/embed/AbAACm1IQE0 should work.
+
+    Using an embedded video has the advantage of not auto-playing more videos
+    while a test is running.
+
+    Partial reference: https://developers.google.com/youtube/iframe_api_reference.
     This reference is useful for site-specific features such as interacting
     with ads, or accessing YouTube's debug data.
     """
 
     _yt_player_state = {
         'UNSTARTED': -1,
         'ENDED': 0,
         'PLAYING': 1,
@@ -32,24 +39,26 @@ class YouTubePuppeteer(VideoPuppeteer):
     }
     _yt_player_state_name = {v: k for k, v in _yt_player_state.items()}
     _time_pattern = re.compile('(?P<minute>\d+):(?P<second>\d+)')
 
     def __init__(self, marionette, url, **kwargs):
         self.player = None
         super(YouTubePuppeteer,
               self).__init__(marionette, url,
-                             video_selector='#movie_player video',
+                             video_selector='.html5-video-player video',
                              **kwargs)
         wait = Wait(self.marionette, timeout=30)
         with self.marionette.using_context(Marionette.CONTEXT_CONTENT):
             verbose_until(wait, self,
-                          expected.element_present(By.ID, 'movie_player'))
-            self.player = self.marionette.find_element(By.ID, 'movie_player')
-            self.marionette.execute_script("log('#movie_player "
+                          expected.element_present(By.CLASS_NAME,
+                                                   'html5-video-player'))
+            self.player = self.marionette.find_element(By.CLASS_NAME,
+                                                       'html5-video-player')
+            self.marionette.execute_script("log('.html5-video-player "
                                            "element obtained');")
         # When an ad is playing, self.player_duration indicates the duration
         # of the spliced-in ad stream, not the duration of the main video, so
         # we attempt to skip the ad first.
         for attempt in range(5):
             sleep(1)
             self.process_ad()
             if (self.ad_inactive and self.duration and not
@@ -112,31 +121,31 @@ class YouTubePuppeteer(VideoPuppeteer):
                 return loads(text)
             except ValueError:
                 self.marionette.log('Error loading json: DebugText',
                                     level='DEBUG')
 
     def execute_yt_script(self, script):
         """
         Execute JS script in content context with access to video element and
-        YouTube #movie_player element.
+        YouTube .html5-video-player element.
 
         :param script: script to be executed.
 
         :return: value returned by script
         """
         with self.marionette.using_context(Marionette.CONTEXT_CONTENT):
             return self.marionette.execute_script(script,
                                                   script_args=[self.video,
                                                                self.player])
 
     @property
     def playback_quality(self):
         """
-        Please see https://developers.google.com/youtube/js_api_reference#Playback_quality
+        Please see https://developers.google.com/youtube/iframe_api_reference#Playback_quality
         for valid values.
 
         :return: A string with a valid value returned via YouTube.
         """
         return self.execute_yt_script('return arguments[1].'
                                       'wrappedJSObject.getPlaybackQuality();')
 
     @property
@@ -171,29 +180,29 @@ class YouTubePuppeteer(VideoPuppeteer):
         return self.execute_yt_script('return arguments[1].'
                                       'wrappedJSObject.getVideoUrl();')
 
     @property
     def player_state(self):
         """
 
         :return: The YouTube state of the video. See
-         https://developers.google.com/youtube/js_api_reference#getPlayerState
+         https://developers.google.com/youtube/iframe_api_reference#getPlayerState
          for valid values.
         """
         state = self.execute_yt_script('return arguments[1].'
                                        'wrappedJSObject.getPlayerState();')
         return state
 
     @property
     def player_unstarted(self):
         """
         This and the following properties are based on the
         player.getPlayerState() call
-        (https://developers.google.com/youtube/js_api_reference#Playback_status)
+        (https://developers.google.com/youtube/iframe_api_reference#Playback_status)
 
         :return: True if the video has not yet started.
         """
         return self.player_state == self._yt_player_state['UNSTARTED']
 
     @property
     def player_ended(self):
         """
@@ -235,17 +244,17 @@ class YouTubePuppeteer(VideoPuppeteer):
         return self.player_state == self._yt_player_state['CUED']
 
     @property
     def ad_state(self):
         """
         Get state of current ad.
 
         :return: Returns one of the constants listed in
-         https://developers.google.com/youtube/js_api_reference#Playback_status
+         https://developers.google.com/youtube/iframe_api_reference#Playback_status
          for an ad.
 
         """
         # Note: ad_state is sometimes not accurate, due to some sort of lag?
         return self.execute_yt_script('return arguments[1].'
                                       'wrappedJSObject.getAdState();')
 
     @property
@@ -345,17 +354,17 @@ class YouTubePuppeteer(VideoPuppeteer):
         """
         if self.ad_playing:
             self.marionette.log('Waiting while ad plays')
             sleep(10)
         else:
             # no ad playing
             return False
         if self.ad_skippable:
-            selector = '#movie_player .videoAdUiSkipContainer'
+            selector = '.html5-video-player .videoAdUiSkipContainer'
             wait = Wait(self.marionette, timeout=30)
             try:
                 with self.marionette.using_context(Marionette.CONTEXT_CONTENT):
                     wait.until(expected.element_displayed(By.CSS_SELECTOR,
                                                           selector))
                     ad_button = self.marionette.find_element(By.CSS_SELECTOR,
                                                              selector)
                     ad_button.click()
@@ -373,17 +382,17 @@ class YouTubePuppeteer(VideoPuppeteer):
         :return: ad duration in seconds, if currently displayed in player
         """
         if not (self.ad_playing or self.player_measure_progress() == 0):
             return None
         # If the ad is not Flash...
         if (self.ad_playing and self.video_src.startswith('mediasource') and
                 self.duration):
             return self.duration
-        selector = '#movie_player .videoAdUiAttribution'
+        selector = '.html5-media-player .videoAdUiAttribution'
         wait = Wait(self.marionette, timeout=5)
         try:
             with self.marionette.using_context(Marionette.CONTEXT_CONTENT):
                 wait.until(expected.element_present(By.CSS_SELECTOR,
                                                     selector))
                 countdown = self.marionette.find_element(By.CSS_SELECTOR,
                                                          selector)
                 ad_time = self._time_pattern.search(countdown.text)
@@ -459,28 +468,28 @@ class YouTubePuppeteer(VideoPuppeteer):
             return False
 
     def __str__(self):
         messages = [super(YouTubePuppeteer, self).__str__()]
         if self.player:
             player_state = self._yt_player_state_name[self.player_state]
             ad_state = self._yt_player_state_name[self.ad_state]
             messages += [
-                '#movie_player: {',
+                '.html5-media-player: {',
                 '\tvideo id: {0},'.format(self.movie_id),
                 '\tvideo_title: {0}'.format(self.movie_title),
                 '\tcurrent_state: {0},'.format(player_state),
                 '\tad_state: {0},'.format(ad_state),
                 '\tplayback_quality: {0},'.format(self.playback_quality),
                 '\tcurrent_time: {0},'.format(self.player_current_time),
                 '\tduration: {0},'.format(self.player_duration),
                 '}'
             ]
         else:
-            messages += ['\t#movie_player: None']
+            messages += ['\t.html5-media-player: None']
         return '\n'.join(messages)
 
 
 def playback_started(yt):
     """
     Check whether playback has started.
 
     :param yt: YouTubePuppeteer

--- a/dom/media/test/external/external_media_tests/urls/default.ini
+++ b/dom/media/test/external/external_media_tests/urls/default.ini
@@ -1,9 +1,9 @@
-# short videos; no ads; max 5 minutes
+# short videos; no ads; embedded; max 5 minutes
 # 0:12
-[https://youtu.be/AbAACm1IQE0]
+[https://youtube.com/embed/AbAACm1IQE0?autoplay=1]
 # 2:18
-[https://www.youtube.com/watch?v=yOQQCoxs8-k]
+[https://youtube.com/embed/yOQQCoxs8-k?autoplay=1]
 # 0:08
-[https://www.youtube.com/watch?v=1visYpIREUM]
+[https://youtube.com/embed/1visYpIREUM?autoplay=1]
 # 2:09
-[https://www.youtube.com/watch?v=rjmuKV9BTkE]
+[https://youtube.com/embed/rjmuKV9BTkE?autoplay=1]

--- a/dom/media/test/external/external_media_tests/urls/youtube/long1-720.ini
+++ b/dom/media/test/external/external_media_tests/urls/youtube/long1-720.ini
@@ -1,14 +1,5 @@
-# all long videos; < 12 hours total
-# 2:18:00
-[http://youtu.be/FLX64H5FYa8]
-# 1:00:00
-[https://www.youtube.com/watch?v=AYYDshv8C4g]
-# 1:10:00
-[https://www.youtube.com/watch?v=V0Vy4kYAPDk]
-# 1:47:00
-[https://www.youtube.com/watch?v=bFtGE2C7Pxs]
-
-
-# shutdownhang | WaitForSingleObjectEx | WaitForSingleObject | PR_Wait | nsThread::ProcessNextEvent(bool, bool*) | NS_ProcessNextEvent(nsIThread*, bool) | mozilla::MediaShutdownManager::Shutdown()
-# 1:43:00
-[https://www.youtube.com/watch?v=BXMtXpmpXPU]
+# a couple of very long videos, < 12 hours total
+# 6:00:00 - can't embed due to copyright
+[https://www.youtube.com/watch?v=5N8sUccRiTA]
+# 2:09:00
+[https://www.youtube.com/embed/b6q5N16dje4?autoplay=1]

deleted file mode 100644
--- a/dom/media/test/external/external_media_tests/urls/youtube/long2-720.ini
+++ /dev/null
@@ -1,9 +0,0 @@
-# a couple of very long videos, < 12 hours total
-# 6:00:00
-[https://www.youtube.com/watch?v=5N8sUccRiTA]
-# 2:27:00
-[https://www.youtube.com/watch?v=NAVrm3wjzq8]
-# 58:50
-[https://www.youtube.com/watch?v=uP1BBw3IYco]
-# 2:09:00
-[https://www.youtube.com/watch?v=b6q5N16dje4]

rename from dom/media/test/external/external_media_tests/urls/youtube/long3-crashes-720.ini
rename to dom/media/test/external/external_media_tests/urls/youtube/long2-crashes-720.ini
--- a/dom/media/test/external/external_media_tests/urls/youtube/long3-crashes-720.ini
+++ b/dom/media/test/external/external_media_tests/urls/youtube/long2-crashes-720.ini
@@ -1,8 +1,11 @@
+# It appears these are not currently used by tests. They are left here as they
+# reference failure scenarios. If tese are fixed that can be removed.
+
 # videos from crashes, < 12 hours
 
 # hang | NtUserMessageCall | SendMessageW
 # 1:10:00
 [https://www.youtube.com/watch?v=Ztie4DqeOak]
 
 # nsPluginInstanceOwner::GetDocument(nsIDocument**)
 # 22:40

rename from dom/media/test/external/external_media_tests/urls/youtube/long4-crashes-900.ini
rename to dom/media/test/external/external_media_tests/urls/youtube/long3-crashes-900.ini
--- a/dom/media/test/external/external_media_tests/urls/youtube/long4-crashes-900.ini
+++ b/dom/media/test/external/external_media_tests/urls/youtube/long3-crashes-900.ini
@@ -1,8 +1,11 @@
+# It appears these are not currently used by tests. They are left here as they
+# reference failure scenarios. If tese are fixed that can be removed.
+
 # Total time: about 12-13 hours + unskippable ads
 #Request url:  https://crash-stats.mozilla.com/api/SuperSearchUnredacted/?product=Firefox&url=%24https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D&url=%21~list&url=%21~index&_results_number=50&platform=Windows&version=37.0&date=%3E2015-03-26
 
 #Request url:    https://crash-stats.mozilla.com/api/SuperSearchUnredacted/?product=Firefox&url=%24https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D&url=%21~list&url=%21~index&_results_number=5&platform=Windows&version=37.0&signature=%3Dhang+%7C+NtUserMessageCall+%7C+SendMessageW&date=%3E2015-03-26
 
 #Request url:    https://crash-stats.mozilla.com/api/SuperSearchUnredacted/?product=Firefox&url=%24https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D&url=%21~list&url=%21~index&_results_number=5&platform=Windows&version=37.0&signature=%3DOOM+%7C+small&date=%3E2015-03-26
 
 #Request url:    https://crash-stats.mozilla.com/api/SuperSearchUnredacted/?product=Firefox&url=%24https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D&url=%21~list&url=%21~index&_results_number=5&platform=Windows&version=37.0&signature=%3Dmozilla%3A%3Alayers%3A%3ACompositorD3D11%3A%3AHandleError%28long%2C+mozilla%3A%3Alayers%3A%3ACompositorD3D11%3A%3ASeverity%29+%7C+mozilla%3A%3Alayers%3A%3ACompositorD3D11%3A%3AFailed%28long%2C+mozilla%3A%3Alayers%3A%3ACompositorD3D11%3A%3ASeverity%29+%7C+mozilla%3A%3Alayers%3A%3ACompositorD3D11%3A%3AUpdateRenderTarget%28%29&date=%3E2015-03-26

deleted file mode 100644
--- a/dom/media/test/external/external_media_tests/urls/youtube/massive-6000.ini
+++ /dev/null
@@ -1,15 +0,0 @@
-# very long test; 96-100 hours?
-# 00:3:26
-[https://www.youtube.com/watch?v=7RMQksXpQSk]
-# nyan cat 10 hours
-[http://youtu.be/9bZkp7q19f0]
-# 4:54:00
-[https://www.youtube.com/watch?v=jWlKjw3LBDk]
-# 3:00:01
-[https://www.youtube.com/watch?v=ub9JUDS_6i8]
-# 10 hours rick roll
-[https://www.youtube.com/watch?v=BROWqjuTM0g]
-# 24 hours
-[https://www.youtube.com/watch?v=FvHiLLkPhQE]
-# 2 hours
-[https://www.youtube.com/watch?v=VmOuW5zTt9w

--- a/dom/media/test/external/external_media_tests/urls/youtube/medium1-60.ini
+++ b/dom/media/test/external/external_media_tests/urls/youtube/medium1-60.ini
@@ -1,18 +1,18 @@
 # mix of shorter/longer videos with/without ads, < 60 min
-# 4:59
-[http://youtu.be/pWI8RB2dmfU]
+# 4:59 - can't embed
+[https://www.youtube.com/watch?v=pWI8RB2dmfU]
 # 0:46 ad at start
-[http://youtu.be/6SFp1z7uA6g]
+[https://www.youtube.com/embed/6SFp1z7uA6g?autoplay=1]
 # 0:58 ad at start
-[http://youtu.be/Aebs62bX0dA]
+[https://www.youtube.com/embed/Aebs62bX0dA?autoplay=1]
 # 1:43 ad
-[https://www.youtube.com/watch?v=l5ODwR6FPRQ]
-# 8:00 ad
+[https://www.youtube.com/embed/l5ODwR6FPRQ?autoplay=1]
+# 8:00 ad - can't embed
 [https://www.youtube.com/watch?v=KlyXNRrsk4A]
 # video with ad in beginning and in the middle 20:00
 # https://bugzilla.mozilla.org/show_bug.cgi?id=1176815
-[https://www.youtube.com/watch?v=cht9Xq9suGg]
+[https://www.youtube.com/embed/cht9Xq9suGg?autoplay=1]
 # 1:35 ad
-[https://www.youtube.com/watch?v=orybDrUj4vA]
-# 3:02 - ad
-[https://youtu.be/tDDVAErOI5U]
+[https://www.youtube.com/embed/orybDrUj4vA?autoplay=1]
+# 3:02 ad
+[https://www.youtube.com/embed/tDDVAErOI5U?autoplay=1]

deleted file mode 100644
--- a/dom/media/test/external/external_media_tests/urls/youtube/medium2-60.ini
+++ /dev/null
@@ -1,6 +0,0 @@
-# a few longer videos, < 60 min total
-# 0:30:00 no ad
-[https://www.youtube.com/watch?v=-qXxNPvqHtQ]
-# 0:20:00
-[http://youtu.be/Fu2DcHzokew]
-

deleted file mode 100644
--- a/dom/media/test/external/external_media_tests/urls/youtube/medium3-120.ini
+++ /dev/null
@@ -1,11 +0,0 @@
-# a few longer videos, < 120 min total
-# video with ad in the middle
-# 21:00
-[https://www.youtube.com/watch?v=cht9Xq9suGg]
-# 16:00
-[https://www.youtube.com/watch?v=6Lm9EHhbJAY]
-# 20:00
-[https://www.youtube.com/watch?v=8XQ1onjXJK0]
-# 59:06
-[https://www.youtube.com/watch?v=kmpiY5kssU4]
-

rename from dom/media/test/external/external_media_tests/urls/youtube/short0-10.ini
rename to dom/media/test/external/external_media_tests/urls/youtube/short1-10.ini

deleted file mode 100644
--- a/dom/media/test/external/external_media_tests/urls/youtube/short1-15.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-# 00:12
-[https://youtu.be/AbAACm1IQE0]
-# longer video with ads; < 15 min total
-# 13:40
-[https://www.youtube.com/watch?v=87uo2TPrsl8]

deleted file mode 100644
--- a/dom/media/test/external/external_media_tests/urls/youtube/short2-15.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-# 1-2 longer videos with ads; < 15 minutes total
-[https://www.youtube.com/watch?v=v678Em6qyzk]
-[https://www.youtube.com/watch?v=l8XOZJkozfI]
-
-

rename from dom/media/test/external/external_media_tests/urls/youtube/short3-crashes-15.ini
rename to dom/media/test/external/external_media_tests/urls/youtube/short2-crashes-15.ini
--- a/dom/media/test/external/external_media_tests/urls/youtube/short3-crashes-15.ini
+++ b/dom/media/test/external/external_media_tests/urls/youtube/short2-crashes-15.ini
@@ -1,8 +1,11 @@
+# It appears these are not currently used by tests. They are left here as they
+# reference failure scenarios. If tese are fixed that can be removed.
+
 # crash-data videos, < 15 minutes total
 
 # hang | NtUserMessageCall | SendMessageW
 # 5:40
 [https://www.youtube.com/watch?v=UIobdRNLNek]
 
 # F1398665248_____________________________
 # 3:59

--- a/dom/plugins/base/npapi.h
+++ b/dom/plugins/base/npapi.h
@@ -41,16 +41,17 @@
 #endif
 #endif
 
 #if defined(XP_UNIX)
 #include <stdio.h>
 #if defined(MOZ_X11)
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include "X11UndefineNone.h"
 #endif
 #endif
 
 #if defined(XP_SYMBIAN)
 #include <QEvent>
 #include <QRegion>
 #endif
 

--- a/dom/plugins/base/nsPluginInstanceOwner.cpp
+++ b/dom/plugins/base/nsPluginInstanceOwner.cpp
@@ -2605,17 +2605,17 @@ nsEventStatus nsPluginInstanceOwner::Pro
         // Get reference point relative to screen:
         LayoutDeviceIntPoint rootPoint(-1, -1);
         if (widget) {
           rootPoint = anEvent.mRefPoint + widget->WidgetToScreenOffset();
         }
 #ifdef MOZ_WIDGET_GTK
         Window root = GDK_ROOT_WINDOW();
 #else
-        Window root = None; // Could XQueryTree, but this is not important.
+        Window root = X11None; // Could XQueryTree, but this is not important.
 #endif
 
         switch (anEvent.mMessage) {
           case eMouseOver:
           case eMouseOut:
             {
               XCrossingEvent& event = pluginEvent.xcrossing;
               event.type = anEvent.mMessage == eMouseOver ?
@@ -2623,17 +2623,17 @@ nsEventStatus nsPluginInstanceOwner::Pro
               event.root = root;
               event.time = anEvent.mTime;
               event.x = pluginPoint.x;
               event.y = pluginPoint.y;
               event.x_root = rootPoint.x;
               event.y_root = rootPoint.y;
               event.state = XInputEventState(mouseEvent);
               // information lost
-              event.subwindow = None;
+              event.subwindow = X11None;
               event.mode = -1;
               event.detail = NotifyDetailNone;
               event.same_screen = True;
               event.focus = mContentFocused;
             }
             break;
           case eMouseMove:
             {
@@ -2642,17 +2642,17 @@ nsEventStatus nsPluginInstanceOwner::Pro
               event.root = root;
               event.time = anEvent.mTime;
               event.x = pluginPoint.x;
               event.y = pluginPoint.y;
               event.x_root = rootPoint.x;
               event.y_root = rootPoint.y;
               event.state = XInputEventState(mouseEvent);
               // information lost
-              event.subwindow = None;
+              event.subwindow = X11None;
               event.is_hint = NotifyNormal;
               event.same_screen = True;
             }
             break;
           case eMouseDown:
           case eMouseUp:
             {
               XButtonEvent& event = pluginEvent.xbutton;
@@ -2673,17 +2673,17 @@ nsEventStatus nsPluginInstanceOwner::Pro
                 case WidgetMouseEvent::eRightButton:
                   event.button = 3;
                   break;
                 default: // WidgetMouseEvent::eLeftButton;
                   event.button = 1;
                   break;
                 }
               // information lost:
-              event.subwindow = None;
+              event.subwindow = X11None;
               event.same_screen = True;
             }
             break;
           default:
             break;
           }
       }
       break;
@@ -2717,17 +2717,17 @@ nsEventStatus nsPluginInstanceOwner::Pro
               break;
             default:
               break;
             }
 #endif
 
           // Information that could be obtained from pluginEvent but we may not
           // want to promise to provide:
-          event.subwindow = None;
+          event.subwindow = X11None;
           event.x = 0;
           event.y = 0;
           event.x_root = -1;
           event.y_root = -1;
           event.same_screen = False;
         }
       else
         {
@@ -2759,17 +2759,17 @@ nsEventStatus nsPluginInstanceOwner::Pro
   if (!pluginEvent.type) {
     return rv;
   }
 
   // Fill in (useless) generic event information.
   XAnyEvent& event = pluginEvent.xany;
   event.display = widget ?
     static_cast<Display*>(widget->GetNativeData(NS_NATIVE_DISPLAY)) : nullptr;
-  event.window = None; // not a real window
+  event.window = X11None; // not a real window
   // information lost:
   event.serial = 0;
   event.send_event = False;
 
   int16_t response = kNPEventNotHandled;
   mInstance->HandleEvent(&pluginEvent, &response, NS_PLUGIN_CALL_SAFE_TO_REENTER_GECKO);
   if (response == kNPEventHandled)
     rv = nsEventStatus_eConsumeNoDefault;

--- a/dom/plugins/base/nsPluginNativeWindowGtk.cpp
+++ b/dom/plugins/base/nsPluginNativeWindowGtk.cpp
@@ -212,17 +212,17 @@ nsresult nsPluginNativeWindowGtk::Create
     return NS_ERROR_FAILURE;
 
   mWsInfo.display = GDK_WINDOW_XDISPLAY(gdkWindow);
 #if (MOZ_WIDGET_GTK == 2)
   mWsInfo.colormap = GDK_COLORMAP_XCOLORMAP(gdk_drawable_get_colormap(gdkWindow));
   GdkVisual* gdkVisual = gdk_drawable_get_visual(gdkWindow);
   mWsInfo.depth = gdkVisual->depth;
 #else
-  mWsInfo.colormap = None;
+  mWsInfo.colormap = X11None;
   GdkVisual* gdkVisual = gdk_window_get_visual(gdkWindow);
   mWsInfo.depth = gdk_visual_get_depth(gdkVisual);
 #endif
   mWsInfo.visual = GDK_VISUAL_XVISUAL(gdkVisual);
     
   return NS_OK;
 }
 

--- a/dom/plugins/ipc/PluginInstanceChild.cpp
+++ b/dom/plugins/ipc/PluginInstanceChild.cpp
@@ -1277,17 +1277,17 @@ PluginInstanceChild::AnswerNPP_SetWindow
                 // workaround https://bugzilla.gnome.org/show_bug.cgi?id=607061
                 // See wrap_gtk_plug_embedded in PluginModuleChild.cpp.
                 g_object_set_data(G_OBJECT(socket_window),
                                   "moz-existed-before-set-window",
                                   GUINT_TO_POINTER(1));
             }
         }
 
-        if (aWindow.visualID != None
+        if (aWindow.visualID != X11None
             && gtk_check_version(2, 12, 10) != nullptr) { // older
             // Workaround for a bug in Gtk+ (prior to 2.12.10) where deleting
             // a foreign GdkColormap will also free the XColormap.
             // http://git.gnome.org/browse/gtk+/log/gdk/x11/gdkcolor-x11.c?id=GTK_2_12_10
             GdkVisual *gdkvisual = gdkx_visual_get(aWindow.visualID);
             GdkColormap *gdkcolor =
                 gdk_x11_colormap_foreign_new(gdkvisual, aWindow.colormap);
 

--- a/dom/plugins/test/testplugin/nptest_gtk2.cpp
+++ b/dom/plugins/test/testplugin/nptest_gtk2.cpp
@@ -76,33 +76,33 @@ pluginInstanceInit(InstanceData* instanc
 #ifdef MOZ_X11
   instanceData->platformData = static_cast<PlatformData*>
     (NPN_MemAlloc(sizeof(PlatformData)));
   if (!instanceData->platformData)
     return NPERR_OUT_OF_MEMORY_ERROR;
 
   instanceData->platformData->display = nullptr;
   instanceData->platformData->visual = nullptr;
-  instanceData->platformData->colormap = None;  
+  instanceData->platformData->colormap = X11None;
   instanceData->platformData->plug = nullptr;
 
   return NPERR_NO_ERROR;
 #else
   // we only support X11 here, since thats what the plugin system uses
   return NPERR_INCOMPATIBLE_VERSION_ERROR;
 #endif
 }
 
 void
 pluginInstanceShutdown(InstanceData* instanceData)
 {
   if (instanceData->hasWidget) {
     Window window = reinterpret_cast<XID>(instanceData->window.window);
 
-    if (window != None) {
+    if (window != X11None) {
       // This window XID should still be valid.
       // See bug 429604 and bug 454756.
       XWindowAttributes attributes;
       if (!XGetWindowAttributes(instanceData->platformData->display, window,
                                 &attributes))
         g_error("XGetWindowAttributes failed at plugin instance shutdown");
     }
   }

--- a/gfx/2d/BorrowedContext.h
+++ b/gfx/2d/BorrowedContext.h
@@ -6,16 +6,17 @@
 #ifndef _MOZILLA_GFX_BORROWED_CONTEXT_H
 #define _MOZILLA_GFX_BORROWED_CONTEXT_H
 
 #include "2D.h"
 
 #ifdef MOZ_X11
 #include <X11/extensions/Xrender.h>
 #include <X11/Xlib.h>
+#include "X11UndefineNone.h"
 #endif
 
 struct _cairo;
 typedef struct _cairo cairo_t;
 
 namespace mozilla {
 
 namespace gfx {
@@ -82,26 +83,26 @@ private:
  * to see if it succeeded. The DrawTarget should not be used while
  * the drawable is borrowed. */
 class BorrowedXlibDrawable
 {
 public:
   BorrowedXlibDrawable()
     : mDT(nullptr),
       mDisplay(nullptr),
-      mDrawable(None),
+      mDrawable(X11None),
       mScreen(nullptr),
       mVisual(nullptr),
       mXRenderFormat(nullptr)
   {}
 
   explicit BorrowedXlibDrawable(DrawTarget *aDT)
     : mDT(nullptr),
       mDisplay(nullptr),
-      mDrawable(None),
+      mDrawable(X11None),
       mScreen(nullptr),
       mVisual(nullptr),
       mXRenderFormat(nullptr)
   {
     Init(aDT);
   }
 
   // We can optionally Init after construction in

--- a/gfx/2d/DrawTargetCairo.cpp
+++ b/gfx/2d/DrawTargetCairo.cpp
@@ -2158,17 +2158,17 @@ DrawTargetCairo::Draw3DTransformedSurfac
   XRenderSetPictureTransform(display, srcPict, (XTransform*)&xform);
 
   Picture dstPict = XRenderCreatePicture(display,
                                          cairo_xlib_surface_get_drawable(xformSurf),
                                          cairo_xlib_surface_get_xrender_format(xformSurf),
                                          0, nullptr);
 
   XRenderComposite(display, PictOpSrc,
-                   srcPict, None, dstPict,
+                   srcPict, X11None, dstPict,
                    0, 0, 0, 0, 0, 0,
                    xformBounds.width, xformBounds.height);
 
   XRenderFreePicture(display, srcPict);
   XRenderFreePicture(display, dstPict);
 
   cairo_device_release(device);
   cairo_surface_mark_dirty(xformSurf);
@@ -2308,17 +2308,17 @@ BorrowedCairoContext::ReturnCairoContext
 
 #ifdef MOZ_X11
 bool
 BorrowedXlibDrawable::Init(DrawTarget* aDT)
 {
   MOZ_ASSERT(aDT, "Caller should check for nullptr");
   MOZ_ASSERT(!mDT, "Can't initialize twice!");
   mDT = aDT;
-  mDrawable = None;
+  mDrawable = X11None;
 
 #ifdef CAIRO_HAS_XLIB_SURFACE
   if (aDT->GetBackendType() != BackendType::CAIRO ||
       aDT->IsDualDrawTarget() ||
       aDT->IsTiledDrawTarget()) {
     return false;
   }
 
@@ -2351,15 +2351,15 @@ BorrowedXlibDrawable::Init(DrawTarget* a
 
 void
 BorrowedXlibDrawable::Finish()
 {
   DrawTargetCairo* cairoDT = static_cast<DrawTargetCairo*>(mDT);
   cairo_surface_t* surf = cairo_get_group_target(cairoDT->mContext);
   cairo_surface_mark_dirty(surf);
   if (mDrawable) {
-    mDrawable = None;
+    mDrawable = X11None;
   }
 }
 #endif
 
 } // namespace gfx
 } // namespace mozilla