--- a/Makefile.in
+++ b/Makefile.in
@@ -28,18 +28,18 @@ DIST_GARBAGE = config.cache config.log c
    config/autoconf.mk \
    mozilla-config.h \
    netwerk/necko-config.h xpcom/xpcom-config.h xpcom/xpcom-private.h \
    .mozconfig.mk
 
 ifndef MOZ_PROFILE_USE
 # Automation builds should always have a new buildid, but for the sake of not
 # re-linking libxul on every incremental build we do not enforce this for
-# developer builds.
-ifneq (,$(MOZ_AUTOMATION)$(MOZ_BUILD_DATE))
+# developer builds.  Tests always need a new buildid as well.
+ifneq (,$(MOZ_AUTOMATION)$(MOZ_BUILD_DATE)$(TEST_MOZBUILD))
 buildid.h source-repo.h: FORCE
 endif
 endif
 
 ifdef JS_STANDALONE
 configure_dir = $(topsrcdir)/js/src
 else
 configure_dir = $(topsrcdir)
@@ -104,17 +104,17 @@ include $(topsrcdir)/build/rebuild-backe
 
 Makefile: $(BUILD_BACKEND_FILES)
 	@$(TOUCH) $@
 
 default:: $(BUILD_BACKEND_FILES)
 endif
 
 install_manifests := \
-  $(addprefix dist/,branding idl include public private xpi-stage) \
+  $(addprefix dist/,branding include public private xpi-stage) \
   _tests \
   $(NULL)
 # Skip the dist/bin install manifest when using the hybrid
 # FasterMake/RecursiveMake backend. This is a hack until bug 1241744 moves
 # xpidl handling to FasterMake in that case, mechanically making the dist/bin
 # install manifest non-existent (non-existent manifests being skipped)
 ifeq (,$(filter FasterMake+RecursiveMake,$(BUILD_BACKENDS)))
 install_manifests += dist/bin
@@ -135,22 +135,20 @@ install_manifest_depends += \
 endif
 endif
 
 .PHONY: install-manifests
 install-manifests: $(addprefix install-,$(install_manifests))
 
 # If we're using the hybrid FasterMake/RecursiveMake backend, we want
 # to recurse in the faster/ directory in parallel of install manifests.
-# But dist/idl needs to happen before (cf. dependencies in
-# config/faster/rules.mk)
 ifneq (,$(filter FasterMake+RecursiveMake,$(BUILD_BACKENDS)))
 install-manifests: faster
 .PHONY: faster
-faster: install-dist/idl
+faster:
 	$(MAKE) -C faster FASTER_RECURSIVE_MAKE=1
 endif
 
 .PHONY: $(addprefix install-,$(install_manifests))
 $(addprefix install-,$(install_manifests)): install-%: $(install_manifest_depends)
 ifneq (,$(filter FasterMake+RecursiveMake,$(BUILD_BACKENDS)))
 	@# If we're using the hybrid FasterMake/RecursiveMake backend, we want
 	@# to ensure the FasterMake end doesn't have install manifests for the

--- a/accessible/base/AccIterator.cpp
+++ b/accessible/base/AccIterator.cpp
@@ -377,17 +377,17 @@ ItemIterator::Next()
   return mAnchor ? (mAnchor = AccGroupInfo::NextItemTo(mAnchor)) : nullptr;
 }
 
 
 ////////////////////////////////////////////////////////////////////////////////
 // XULTreeItemIterator
 ////////////////////////////////////////////////////////////////////////////////
 
-XULTreeItemIterator::XULTreeItemIterator(XULTreeAccessible* aXULTree,
+XULTreeItemIterator::XULTreeItemIterator(const XULTreeAccessible* aXULTree,
                                          nsITreeView* aTreeView,
                                          int32_t aRowIdx) :
   mXULTree(aXULTree), mTreeView(aTreeView), mRowCount(-1),
   mContainerLevel(-1), mCurrRowIdx(aRowIdx + 1)
 {
   mTreeView->GetRowCount(&mRowCount);
   if (aRowIdx != -1)
     mTreeView->GetLevel(aRowIdx, &mContainerLevel);

--- a/accessible/base/AccIterator.h
+++ b/accessible/base/AccIterator.h
@@ -296,28 +296,28 @@ private:
 
 
 /**
  * Used to iterate through XUL tree items of the same level.
  */
 class XULTreeItemIterator : public AccIterable
 {
 public:
-  XULTreeItemIterator(XULTreeAccessible* aXULTree, nsITreeView* aTreeView,
+  XULTreeItemIterator(const XULTreeAccessible* aXULTree, nsITreeView* aTreeView,
                       int32_t aRowIdx);
   virtual ~XULTreeItemIterator() { }
 
   virtual Accessible* Next() override;
 
 private:
   XULTreeItemIterator() = delete;
   XULTreeItemIterator(const XULTreeItemIterator&) = delete;
   XULTreeItemIterator& operator = (const XULTreeItemIterator&) = delete;
 
-  XULTreeAccessible* mXULTree;
+  const XULTreeAccessible* mXULTree;
   nsITreeView* mTreeView;
   int32_t mRowCount;
   int32_t mContainerLevel;
   int32_t mCurrRowIdx;
 };
 
 } // namespace a11y
 } // namespace mozilla

--- a/accessible/base/MarkupMap.h
+++ b/accessible/base/MarkupMap.h
@@ -322,17 +322,18 @@ MARKUPMAP(section,
 
 MARKUPMAP(summary,
           New_HTMLSummary,
           roles::SUMMARY)
 
 MARKUPMAP(
   table,
   [](Element* aElement, Accessible* aContext) -> Accessible* {
-     if (aElement->GetPrimaryFrame()->AccessibleType() != eHTMLTableType) {
+     if (aElement->GetPrimaryFrame() &&
+         aElement->GetPrimaryFrame()->AccessibleType() != eHTMLTableType) {
        return new ARIAGridAccessibleWrap(aElement, aContext->Document());
      }
      return nullptr;
   },
   0
 )
 
 MARKUPMAP(time,
@@ -385,22 +386,23 @@ MARKUPMAP(
      // CreateAccessibleByFrameType dual logic.
      Accessible* table = aContext->IsTable() ? aContext : nullptr;
      if (!table && aContext->Parent() && aContext->Parent()->IsTable()) {
         table = aContext->Parent();
      }
      if (table) {
         nsIContent* parentContent = aElement->GetParent();
         nsIFrame* parentFrame = parentContent->GetPrimaryFrame();
-        if (!parentFrame->IsTableWrapperFrame()) {
+        if (parentFrame && !parentFrame->IsTableWrapperFrame()) {
           parentContent = parentContent->GetParent();
           parentFrame = parentContent->GetPrimaryFrame();
           if (table->GetContent() == parentContent &&
-              (!parentFrame->IsTableWrapperFrame() ||
-               aElement->GetPrimaryFrame()->AccessibleType() != eHTMLTableRowType)) {
+              ((parentFrame && !parentFrame->IsTableWrapperFrame()) ||
+               (aElement->GetPrimaryFrame() &&
+                aElement->GetPrimaryFrame()->AccessibleType() != eHTMLTableRowType))) {
             return new ARIARowAccessible(aElement, aContext->Document());
           }
         }
       }
       return nullptr;
   },
   0
 )

--- a/accessible/base/nsAccessibilityService.cpp
+++ b/accessible/base/nsAccessibilityService.cpp
@@ -1049,16 +1049,30 @@ nsAccessibilityService::CreateAccessible
     return nullptr;
 
   nsIContent* content = aNode->AsContent();
   nsIFrame* frame = content->GetPrimaryFrame();
 
   // Check frame and its visibility. Note, hidden frame allows visible
   // elements in subtree.
   if (!frame || !frame->StyleVisibility()->IsVisible()) {
+    // display:contents element doesn't have a frame, but retains the semantics.
+    // All its children are unaffected.
+    if (content->IsElement() && content->AsElement()->IsDisplayContents()) {
+      const HTMLMarkupMapInfo* markupMap =
+        mHTMLMarkupMap.Get(content->NodeInfo()->NameAtom());
+      if (markupMap && markupMap->new_func) {
+        RefPtr<Accessible> newAcc =
+          markupMap->new_func(content->AsElement(), aContext);
+        document->BindToDocument(newAcc, aria::GetRoleMap(content->AsElement()));
+        return newAcc;
+      }
+      return nullptr;
+    }
+
     if (aIsSubtreeHidden && !frame)
       *aIsSubtreeHidden = true;
 
     return nullptr;
   }
 
   if (frame->GetContent() != content) {
     // Not the main content for this frame. This happens because <area>

--- a/accessible/generic/Accessible.cpp
+++ b/accessible/generic/Accessible.cpp
@@ -319,18 +319,24 @@ Accessible::TranslateString(const nsStri
   if (NS_SUCCEEDED(rv))
     aStringOut.Assign(xsValue);
 }
 
 uint64_t
 Accessible::VisibilityState() const
 {
   nsIFrame* frame = GetFrame();
-  if (!frame)
+  if (!frame) {
+    // Element having display:contents is considered visible semantically,
+    // despite it doesn't have a visually visible box.
+    if (mContent->IsElement() && mContent->AsElement()->IsDisplayContents()) {
+      return states::OFFSCREEN;
+    }
     return states::INVISIBLE;
+  }
 
   // Walk the parent frame chain to see if there's invisible parent or the frame
   // is in background tab.
   if (!frame->StyleVisibility()->IsVisible())
     return states::INVISIBLE;
 
   // Offscreen state if the document's visibility state is not visible.
   if (Document()->IsHidden())
@@ -1941,18 +1947,22 @@ Accessible::AppendTextTo(nsAString& aTex
                          uint32_t aLength)
 {
   // Return text representation of non-text accessible within hypertext
   // accessible. Text accessible overrides this method to return enclosed text.
   if (aStartOffset != 0 || aLength == 0)
     return;
 
   nsIFrame *frame = GetFrame();
-  if (!frame)
+  if (!frame) {
+    if (mContent->IsElement() && mContent->AsElement()->IsDisplayContents()) {
+      aText += kEmbeddedObjectChar;
+    }
     return;
+  }
 
   NS_ASSERTION(mParent,
                "Called on accessible unbound from tree. Result can be wrong.");
 
   if (frame->IsBrFrame()) {
     aText += kForcedNewLineChar;
   } else if (mParent && nsAccUtils::MustPrune(mParent)) {
     // Expose the embedded object accessible as imaginary embedded object
@@ -2559,17 +2569,17 @@ bool
 Accessible::AreItemsOperable() const
 {
   return HasOwnContent() &&
     mContent->IsElement() &&
     mContent->AsElement()->HasAttr(kNameSpaceID_None, nsGkAtoms::aria_activedescendant);
 }
 
 Accessible*
-Accessible::CurrentItem()
+Accessible::CurrentItem() const
 {
   // Check for aria-activedescendant, which changes which element has focus.
   // For activedescendant, the ARIA spec does not require that the user agent
   // checks whether pointed node is actually a DOM descendant of the element
   // with the aria-activedescendant attribute.
   nsAutoString id;
   if (HasOwnContent() &&
       mContent->IsElement() &&
@@ -2582,17 +2592,17 @@ Accessible::CurrentItem()
       if (document)
         return document->GetAccessible(activeDescendantElm);
     }
   }
   return nullptr;
 }
 
 void
-Accessible::SetCurrentItem(Accessible* aItem)
+Accessible::SetCurrentItem(const Accessible* aItem)
 {
   nsAtom* id = aItem->GetContent()->GetID();
   if (id) {
     nsAutoString idStr;
     id->ToString(idStr);
     mContent->AsElement()->SetAttr(kNameSpaceID_None,
                                    nsGkAtoms::aria_activedescendant,
                                    idStr,

--- a/accessible/generic/Accessible.h
+++ b/accessible/generic/Accessible.h
@@ -430,17 +430,17 @@ public:
   /**
    * Return index in parent accessible.
    */
   virtual int32_t IndexInParent() const;
 
   /**
    * Return true if accessible has children;
    */
-  bool HasChildren() { return !!GetChildAt(0); }
+  bool HasChildren() const { return !!GetChildAt(0); }
 
   /**
    * Return first/last/next/previous sibling of the accessible.
    */
   inline Accessible* NextSibling() const
     {  return GetSiblingAtOffset(1); }
   inline Accessible* PrevSibling() const
     { return GetSiblingAtOffset(-1); }
@@ -845,22 +845,22 @@ public:
    * can be activated.
    */
   virtual bool AreItemsOperable() const;
 
   /**
    * Return the current item of the widget, i.e. an item that has or will have
    * keyboard focus when widget gets active.
    */
-  virtual Accessible* CurrentItem();
+  virtual Accessible* CurrentItem() const;
 
   /**
    * Set the current item of the widget.
    */
-  virtual void SetCurrentItem(Accessible* aItem);
+  virtual void SetCurrentItem(const Accessible* aItem);
 
   /**
    * Return container widget this accessible belongs to.
    */
   virtual Accessible* ContainerWidget() const;
 
   /**
    * Return the localized string for the given key.

--- a/accessible/generic/RootAccessible.cpp
+++ b/accessible/generic/RootAccessible.cpp
@@ -97,17 +97,17 @@ RootAccessible::NativeRole() const
     return roles::DIALOG;
 
   return DocAccessibleWrap::NativeRole();
 }
 
 // RootAccessible protected member
 #ifdef MOZ_XUL
 uint32_t
-RootAccessible::GetChromeFlags()
+RootAccessible::GetChromeFlags() const
 {
   // Return the flag set for the top level window as defined
   // by nsIWebBrowserChrome::CHROME_WINDOW_[FLAGNAME]
   // Not simple: nsIXULWindow is not just a QI from nsIDOMWindow
   nsCOMPtr<nsIDocShell> docShell = nsCoreUtils::GetDocShellFor(mDocumentNode);
   NS_ENSURE_TRUE(docShell, 0);
   nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
   docShell->GetTreeOwner(getter_AddRefs(treeOwner));

--- a/accessible/generic/RootAccessible.h
+++ b/accessible/generic/RootAccessible.h
@@ -71,17 +71,17 @@ protected:
   void HandlePopupHidingEvent(nsINode* aNode);
 
 #ifdef MOZ_XUL
   void HandleTreeRowCountChangedEvent(dom::Event* aEvent,
                                       XULTreeAccessible* aAccessible);
   void HandleTreeInvalidatedEvent(dom::Event* aEvent,
                                   XULTreeAccessible* aAccessible);
 
-    uint32_t GetChromeFlags();
+    uint32_t GetChromeFlags() const;
 #endif
 };
 
 inline RootAccessible*
 Accessible::AsRoot()
 {
   return IsRoot() ? static_cast<mozilla::a11y::RootAccessible*>(this) : nullptr;
 }

--- a/accessible/html/HTMLSelectAccessible.cpp
+++ b/accessible/html/HTMLSelectAccessible.cpp
@@ -88,32 +88,32 @@ HTMLSelectListAccessible::IsActiveWidget
 
 bool
 HTMLSelectListAccessible::AreItemsOperable() const
 {
   return true;
 }
 
 Accessible*
-HTMLSelectListAccessible::CurrentItem()
+HTMLSelectListAccessible::CurrentItem() const
 {
   nsIListControlFrame* listControlFrame = do_QueryFrame(GetFrame());
   if (listControlFrame) {
     nsCOMPtr<nsIContent> activeOptionNode = listControlFrame->GetCurrentOption();
     if (activeOptionNode) {
       DocAccessible* document = Document();
       if (document)
         return document->GetAccessible(activeOptionNode);
     }
   }
   return nullptr;
 }
 
 void
-HTMLSelectListAccessible::SetCurrentItem(Accessible* aItem)
+HTMLSelectListAccessible::SetCurrentItem(const Accessible* aItem)
 {
   if (!aItem->GetContent()->IsElement())
     return;
 
   aItem->GetContent()->AsElement()->SetAttr(kNameSpaceID_None,
                                             nsGkAtoms::selected,
                                             NS_LITERAL_STRING("true"),
                                             true);
@@ -495,23 +495,23 @@ HTMLComboboxAccessible::IsActiveWidget()
 bool
 HTMLComboboxAccessible::AreItemsOperable() const
 {
   nsIComboboxControlFrame* comboboxFrame = do_QueryFrame(GetFrame());
   return comboboxFrame && comboboxFrame->IsDroppedDown();
 }
 
 Accessible*
-HTMLComboboxAccessible::CurrentItem()
+HTMLComboboxAccessible::CurrentItem() const
 {
   return AreItemsOperable() ? mListAccessible->CurrentItem() : nullptr;
 }
 
 void
-HTMLComboboxAccessible::SetCurrentItem(Accessible* aItem)
+HTMLComboboxAccessible::SetCurrentItem(const Accessible* aItem)
 {
   if (AreItemsOperable())
     mListAccessible->SetCurrentItem(aItem);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // HTMLComboboxAccessible: protected
 

--- a/accessible/html/HTMLSelectAccessible.h
+++ b/accessible/html/HTMLSelectAccessible.h
@@ -44,18 +44,18 @@ public:
   // SelectAccessible
   virtual bool SelectAll() override;
   virtual bool UnselectAll() override;
 
   // Widgets
   virtual bool IsWidget() const override;
   virtual bool IsActiveWidget() const override;
   virtual bool AreItemsOperable() const override;
-  virtual Accessible* CurrentItem() override;
-  virtual void SetCurrentItem(Accessible* aItem) override;
+  virtual Accessible* CurrentItem() const override;
+  virtual void SetCurrentItem(const Accessible* aItem) override;
 };
 
 /*
  * Options inside the select, contained within the list
  */
 class HTMLSelectOptionAccessible : public HyperTextAccessibleWrap
 {
 public:
@@ -175,18 +175,18 @@ public:
   virtual uint8_t ActionCount() override;
   virtual void ActionNameAt(uint8_t aIndex, nsAString& aName) override;
   virtual bool DoAction(uint8_t aIndex) override;
 
   // Widgets
   virtual bool IsWidget() const override;
   virtual bool IsActiveWidget() const override;
   virtual bool AreItemsOperable() const override;
-  virtual Accessible* CurrentItem() override;
-  virtual void SetCurrentItem(Accessible* aItem) override;
+  virtual Accessible* CurrentItem() const override;
+  virtual void SetCurrentItem(const Accessible* aItem) override;
 
 protected:
   /**
    * Return selected option.
    */
   Accessible* SelectedOption() const;
 
 private:

--- a/accessible/tests/mochitest/states/test_visibility.html
+++ b/accessible/tests/mochitest/states/test_visibility.html
@@ -18,16 +18,17 @@
   <script type="application/javascript">
     // Tests
 
     function doTests() {
       testStates("div", 0, 0, STATE_INVISIBLE | STATE_OFFSCREEN);
       testStates("div_off", STATE_OFFSCREEN, 0, STATE_INVISIBLE);
       testStates("div_transformed", STATE_OFFSCREEN, 0, STATE_INVISIBLE);
       testStates("div_abschild", 0, 0, STATE_INVISIBLE | STATE_OFFSCREEN);
+      testStates("ul", STATE_OFFSCREEN, 0, STATE_INVISIBLE);
 
       SimpleTest.finish();
     }
 
     SimpleTest.waitForExplicitFinish();
     addA11yLoadEvent(doTests);
   </script>
 
@@ -61,11 +62,15 @@
       transformed!
     </div>
 
     <!-- edge case: no rect but has out of flow child -->
     <div id="div_abschild">
       <p style="position: absolute; left: 120px; top:120px;">absolute</p>
     </div>
 
+    <ul id="ul" style="display: contents;">
+      <li>Supermarket 1</li>
+      <li>Supermarket 2</li>
+    </ul>
   </div>
 </body>
 </html>

--- a/accessible/tests/mochitest/text/test_hypertext.html
+++ b/accessible/tests/mochitest/text/test_hypertext.html
@@ -34,17 +34,17 @@
       // ////////////////////////////////////////////////////////////////////////
       // hypertext
       // ////////////////////////////////////////////////////////////////////////
 
       // ! - embedded object char
       // __h__e__l__l__o__ __!__ __s__e__e__ __!__
       //  0  1  2  3  4  5  6  7  8  9 10 11 12 13
 
-      var IDs = [ "hypertext", "hypertext2" ];
+      var IDs = [ "hypertext", "hypertext2", "ht_displaycontents" ];
 
       // //////////////////////////////////////////////////////////////////////
       // characterCount
 
       testCharacterCount(IDs, 13);
 
       // //////////////////////////////////////////////////////////////////////
       // getText
@@ -118,16 +118,20 @@
   <div id="content" style="display: none"></div>
   <pre id="test">
   </pre>
 
   <div id="nulltext"></div>
 
   <div id="hypertext">hello <a>friend</a> see <img src="about:blank"></div>
   <div id="hypertext2">hello <a>friend</a> see <input></div>
+  <div id="ht_displaycontents">hello <a>friend</a> see <ul id="ul" style="display: contents;">
+    <li>Supermarket 1</li>
+    <li>Supermarket 2</li>
+  </ul></div>
   <ol id="list">
     <li id="listitem">foo</li>
     <li id="listitemnone">bar</li>
   </ol>
 
   <div id="hypertext3">line
 <!-- haha -->
 <!-- hahaha -->

--- a/accessible/tests/mochitest/tree/a11y.ini
+++ b/accessible/tests/mochitest/tree/a11y.ini
@@ -20,16 +20,17 @@ skip-if = true # Bug 561508
 [test_aria_presentation.html]
 [test_aria_table.html]
 [test_brokencontext.html]
 [test_button.xul]
 [test_canvas.html]
 [test_combobox.xul]
 [test_cssflexbox.html]
 [test_cssoverflow.html]
+[test_display_contents.html]
 [test_dochierarchy.html]
 [test_dockids.html]
 [test_filectrl.html]
 [test_formctrl.html]
 skip-if = buildapp == "mulet"
 [test_formctrl.xul]
 [test_gencontent.html]
 [test_groupbox.xul]

new file mode 100644
--- /dev/null
+++ b/accessible/tests/mochitest/tree/test_display_contents.html
@@ -0,0 +1,50 @@
+<!DOCTYPE html>
+<html>
+
+<head>
+<title>CSS display:contents tests</title>
+<link rel="stylesheet" type="text/css"
+      href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+
+<script type="application/javascript"
+        src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+<script type="application/javascript"
+        src="../common.js"></script>
+<script type="application/javascript"
+        src="../role.js"></script>
+
+<script type="application/javascript">
+function doTest() {
+  let tree =
+    { LIST: [
+      { LISTITEM: [
+        { STATICTEXT: [] },
+        { TEXT_LEAF: [] }
+      ]},
+      { LISTITEM: [
+        { STATICTEXT: [] },
+        { TEXT_LEAF: [] }
+      ]},
+    ] };
+  testAccessibleTree("ul", tree);
+
+  SimpleTest.finish();
+}
+
+SimpleTest.waitForExplicitFinish();
+addA11yLoadEvent(doTest);
+</script>
+</head>
+<body>
+  <p id="display"></p>
+  <div id="content" style="display: none"></div>
+  <pre id="test">
+  </pre>
+
+  <ul id="ul" style="display: contents;">
+    <li>Supermarket 1</li>
+    <li>Supermarket 2</li>
+  </ul>
+</body>
+</html>

--- a/accessible/xul/XULMenuAccessible.cpp
+++ b/accessible/xul/XULMenuAccessible.cpp
@@ -568,26 +568,26 @@ XULMenubarAccessible::IsActiveWidget() c
 
 bool
 XULMenubarAccessible::AreItemsOperable() const
 {
   return true;
 }
 
 Accessible*
-XULMenubarAccessible::CurrentItem()
+XULMenubarAccessible::CurrentItem() const
 {
   nsMenuBarFrame* menuBarFrame = do_QueryFrame(GetFrame());
   if (menuBarFrame) {
     nsMenuFrame* menuFrame = menuBarFrame->GetCurrentMenuItem();
     if (menuFrame) {
       nsIContent* menuItemNode = menuFrame->GetContent();
       return mDoc->GetAccessible(menuItemNode);
     }
   }
   return nullptr;
 }
 
 void
-XULMenubarAccessible::SetCurrentItem(Accessible* aItem)
+XULMenubarAccessible::SetCurrentItem(const Accessible* aItem)
 {
   NS_ERROR("XULMenubarAccessible::SetCurrentItem not implemented");
 }

--- a/accessible/xul/XULMenuAccessible.h
+++ b/accessible/xul/XULMenuAccessible.h
@@ -103,18 +103,18 @@ public:
   XULMenubarAccessible(nsIContent* aContent, DocAccessible* aDoc);
 
   // Accessible
   virtual a11y::role NativeRole() const override;
 
   // Widget
   virtual bool IsActiveWidget() const override;
   virtual bool AreItemsOperable() const override;
-  virtual Accessible* CurrentItem() override;
-  virtual void SetCurrentItem(Accessible* aItem) override;
+  virtual Accessible* CurrentItem() const override;
+  virtual void SetCurrentItem(const Accessible* aItem) override;
 
 protected:
   // Accessible
   virtual ENameValueFlag NativeName(nsString& aName) override;
 };
 
 } // namespace a11y
 } // namespace mozilla

--- a/accessible/xul/XULSelectControlAccessible.cpp
+++ b/accessible/xul/XULSelectControlAccessible.cpp
@@ -206,17 +206,17 @@ XULSelectControlAccessible::SelectAll()
   // otherwise, don't support this method
   return false;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // XULSelectControlAccessible: Widgets
 
 Accessible*
-XULSelectControlAccessible::CurrentItem()
+XULSelectControlAccessible::CurrentItem() const
 {
   if (!mSelectControl)
     return nullptr;
 
   nsCOMPtr<nsIDOMXULSelectControlItemElement> currentItemElm;
   nsCOMPtr<nsIDOMXULMultiSelectControlElement> multiSelectControl =
     do_QueryInterface(mSelectControl);
   if (multiSelectControl)
@@ -233,17 +233,17 @@ XULSelectControlAccessible::CurrentItem(
     if (document)
       return document->GetAccessible(DOMNode);
   }
 
   return nullptr;
 }
 
 void
-XULSelectControlAccessible::SetCurrentItem(Accessible* aItem)
+XULSelectControlAccessible::SetCurrentItem(const Accessible* aItem)
 {
   if (!mSelectControl)
     return;
 
   nsCOMPtr<nsIDOMXULSelectControlItemElement> itemElm =
     do_QueryInterface(aItem->GetContent());
   nsCOMPtr<nsIDOMXULMultiSelectControlElement> multiSelectControl =
     do_QueryInterface(mSelectControl);

--- a/accessible/xul/XULSelectControlAccessible.h
+++ b/accessible/xul/XULSelectControlAccessible.h
@@ -31,18 +31,18 @@ public:
   virtual Accessible* GetSelectedItem(uint32_t aIndex) override;
   virtual bool IsItemSelected(uint32_t aIndex) override;
   virtual bool AddItemToSelection(uint32_t aIndex) override;
   virtual bool RemoveItemFromSelection(uint32_t aIndex) override;
   virtual bool SelectAll() override;
   virtual bool UnselectAll() override;
 
   // Widgets
-  virtual Accessible* CurrentItem() override;
-  virtual void SetCurrentItem(Accessible* aItem) override;
+  virtual Accessible* CurrentItem() const override;
+  virtual void SetCurrentItem(const Accessible* aItem) override;
 
 protected:
   // nsIDOMXULMultiSelectControlElement inherits from this, so we'll always have
   // one of these if the widget is valid and not defunct
   nsCOMPtr<nsIDOMXULSelectControlElement> mSelectControl;
 };
 
 } // namespace a11y

--- a/accessible/xul/XULTreeAccessible.cpp
+++ b/accessible/xul/XULTreeAccessible.cpp
@@ -217,17 +217,17 @@ XULTreeAccessible::ChildAtPoint(int32_t 
 
   return child;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // XULTreeAccessible: SelectAccessible
 
 Accessible*
-XULTreeAccessible::CurrentItem()
+XULTreeAccessible::CurrentItem() const
 {
   if (!mTreeView)
     return nullptr;
 
   nsCOMPtr<nsITreeSelection> selection;
   mTreeView->GetSelection(getter_AddRefs(selection));
   if (selection) {
     int32_t currentIndex = -1;
@@ -235,17 +235,17 @@ XULTreeAccessible::CurrentItem()
     if (currentIndex >= 0)
       return GetTreeItemAccessible(currentIndex);
   }
 
   return nullptr;
 }
 
 void
-XULTreeAccessible::SetCurrentItem(Accessible* aItem)
+XULTreeAccessible::SetCurrentItem(const Accessible* aItem)
 {
   NS_ERROR("XULTreeAccessible::SetCurrentItem not implemented");
 }
 
 void
 XULTreeAccessible::SelectedItems(nsTArray<Accessible*>* aItems)
 {
   if (!mTreeView)

--- a/accessible/xul/XULTreeAccessible.h
+++ b/accessible/xul/XULTreeAccessible.h
@@ -59,18 +59,18 @@ public:
   virtual bool RemoveItemFromSelection(uint32_t aIndex) override;
   virtual bool SelectAll() override;
   virtual bool UnselectAll() override;
 
   // Widgets
   virtual bool IsWidget() const override;
   virtual bool IsActiveWidget() const override;
   virtual bool AreItemsOperable() const override;
-  virtual Accessible* CurrentItem() override;
-  virtual void SetCurrentItem(Accessible* aItem) override;
+  virtual Accessible* CurrentItem() const override;
+  virtual void SetCurrentItem(const Accessible* aItem) override;
 
   virtual Accessible* ContainerWidget() const override;
 
   // XULTreeAccessible
 
   /**
    * Return tree item accessible at the givem row. If accessible doesn't exist
    * in the cache then create and cache it.

--- a/config/faster/rules.mk
+++ b/config/faster/rules.mk
@@ -92,24 +92,16 @@ ACDEFINES += -DBUILD_FASTER
 		-DBOOKMARKS_INCLUDE_DIR=$(TOPSRCDIR)/browser/locales/en-US/profile \
 		$(ACDEFINES) \
 		install_$(subst /,_,$*)
 
 # ============================================================================
 # Below is a set of additional dependencies and variables used to build things
 # that are not supported by data in moz.build.
 
-# The xpidl target in config/makefiles/xpidl requires the install manifest for
-# dist/idl to have been processed. When using the hybrid
-# FasterMake/RecursiveMake backend, this dependency is handled in the top-level
-# Makefile.
-ifndef FASTER_RECURSIVE_MAKE
-$(TOPOBJDIR)/config/makefiles/xpidl/xpidl: $(TOPOBJDIR)/install-dist_idl
-endif
-
 $(TOPOBJDIR)/build/application.ini: $(TOPOBJDIR)/buildid.h $(TOPOBJDIR)/source-repo.h
 
 # The manifest of allowed system add-ons should be re-built when using
 # "build faster".
 #
 # Note the dependency on install-dist/bin.  The form of this
 # dependency is critical: it's triggering the stem rule (install-%)
 # above to force the dist/bin manifest to be processed.  The more

--- a/config/makefiles/xpidl/Makefile.in
+++ b/config/makefiles/xpidl/Makefile.in
@@ -36,17 +36,18 @@ code_gen_deps := $(topsrcdir)/xpcom/refl
 
 # TODO we should use py_action, but that would require extra directories to be
 # in the virtualenv.
 %.xpt:
 	$(REPORT_BUILD)
 	$(PYTHON_PATH) $(PLY_INCLUDE) -I$(topsrcdir)/xpcom/idl-parser -I$(DEPTH)/xpcom/idl-parser/xpidl \
 		$(process_py) --cache-dir $(DEPTH)/xpcom/idl-parser/xpidl --depsdir $(idl_deps_dir) \
 		--bindings-conf $(topsrcdir)/dom/bindings/Bindings.conf \
-		$(dist_idl_dir) $(dist_include_dir) $(dist_xpcrs_dir) $(@D) \
+		$(foreach dir,$(all_idl_dirs),-I $(dir)) \
+		$(dist_include_dir) $(dist_xpcrs_dir) $(@D) \
 		$(basename $(notdir $@)) $($(basename $(notdir $@))_deps)
 # When some IDL is added or removed, if the actual IDL file was already, or
 # still is, in the tree, simple dependencies can't detect that the XPT needs
 # to be rebuilt.
 # Add the current value of $($(xpidl_module)_deps) in the depend file, such that
 # we can later check if the value has changed since last build, which will
 # indicate whether IDLs were added or removed.
 # Note that removing previously built files is not covered.
@@ -70,17 +71,16 @@ endif
 $(generated_file): $(xpt_files) $(code_gen_py) $(code_gen_deps)
 	$(REPORT_BUILD)
 	$(PYTHON_PATH) $(PLY_INCLUDE) $(code_gen_py) $(generated_file) $(xpt_files)
 
 -include $(depends_files)
 
 define xpt_deps
 $(1): $(call mkdir_deps,$(dir $(1)))
-$(1): $(addsuffix .idl,$(addprefix $(dist_idl_dir)/,$($(basename $(notdir $(1)))_deps)))
 ifneq ($($(basename $(notdir $(1)))_deps),$($(basename $(notdir $(1)))_deps_built))
 $(1): FORCE
 endif
 endef
 
 $(foreach xpt,$(xpt_files),$(eval $(call xpt_deps,$(xpt))))
 
 .PHONY: xpidl

--- a/devtools/server/actors/object/previewers.js
+++ b/devtools/server/actors/object/previewers.js
@@ -541,17 +541,16 @@ previewers.Object = [
 
   function ArrayLike({obj, hooks}, grip, rawObj) {
     if (isWorker || !rawObj ||
         obj.class != "DOMStringList" &&
         obj.class != "DOMTokenList" &&
         obj.class != "CSSRuleList" &&
         obj.class != "MediaList" &&
         obj.class != "StyleSheetList" &&
-        obj.class != "CSSValueList" &&
         obj.class != "NamedNodeMap" &&
         obj.class != "FileList" &&
         obj.class != "NodeList") {
       return false;
     }
 
     if (typeof rawObj.length != "number") {
       return false;

--- a/dom/base/UseCounters.conf
+++ b/dom/base/UseCounters.conf
@@ -103,13 +103,14 @@ method console.table
 method console.trace
 method console.warn
 method console.dir
 method console.dirxml
 method console.group
 method console.groupCollapsed
 method console.groupEnd
 method console.time
+method console.timeLog
 method console.timeEnd
 method console.exception
 method console.timeStamp
 method console.profile
 method console.profileEnd

--- a/dom/base/WindowNamedPropertiesHandler.cpp
+++ b/dom/base/WindowNamedPropertiesHandler.cpp
@@ -108,52 +108,50 @@ WindowNamedPropertiesHandler::getOwnProp
   nsGlobalWindowInner* win = xpc::WindowOrNull(global);
   if (win->Length() > 0) {
     nsCOMPtr<nsPIDOMWindowOuter> childWin = win->GetChildWindow(str);
     if (childWin && ShouldExposeChildWindow(str, childWin)) {
       // We found a subframe of the right name. Shadowing via |var foo| in
       // global scope is still allowed, since |var| only looks up |own|
       // properties. But unqualified shadowing will fail, per-spec.
       JS::Rooted<JS::Value> v(aCx);
-      if (!WrapObject(aCx, childWin, &v)) {
+      if (!ToJSValue(aCx, nsGlobalWindowOuter::Cast(childWin), &v)) {
         return false;
       }
       FillPropertyDescriptor(aDesc, aProxy, 0, v);
       return true;
     }
   }
 
   // The rest of this function is for HTML documents only.
   nsCOMPtr<nsIHTMLDocument> htmlDoc = do_QueryInterface(win->GetExtantDoc());
   if (!htmlDoc) {
     return true;
   }
   nsHTMLDocument* document = static_cast<nsHTMLDocument*>(htmlDoc.get());
 
+  JS::Rooted<JS::Value> v(aCx);
   Element* element = document->GetElementById(str);
   if (element) {
-    JS::Rooted<JS::Value> v(aCx);
-    if (!WrapObject(aCx, element, &v)) {
+    if (!ToJSValue(aCx, element, &v)) {
       return false;
     }
     FillPropertyDescriptor(aDesc, aProxy, 0, v);
     return true;
   }
 
-  nsWrapperCache* cache;
-  nsISupports* result = document->ResolveName(str, &cache);
-  if (!result) {
-    return true;
+  ErrorResult rv;
+  bool found = document->ResolveName(aCx, str, &v, rv);
+  if (rv.MaybeSetPendingException(aCx)) {
+    return false;
   }
 
-  JS::Rooted<JS::Value> v(aCx);
-  if (!WrapObject(aCx, result, cache, nullptr, &v)) {
-    return false;
+  if (found) {
+    FillPropertyDescriptor(aDesc, aProxy, 0, v);
   }
-  FillPropertyDescriptor(aDesc, aProxy, 0, v);
   return true;
 }
 
 bool
 WindowNamedPropertiesHandler::defineProperty(JSContext* aCx,
                                              JS::Handle<JSObject*> aProxy,
                                              JS::Handle<jsid> aId,
                                              JS::Handle<JS::PropertyDescriptor> aDesc,

--- a/dom/base/moz.build
+++ b/dom/base/moz.build
@@ -75,17 +75,16 @@ EXPORTS += [
     'nsIContent.h',
     'nsIContentInlines.h',
     'nsIContentIterator.h',
     'nsIContentSerializer.h',
     'nsIdentifierMapEntry.h',
     'nsIDocument.h',
     'nsIDocumentInlines.h',
     'nsIDocumentObserver.h',
-    'nsIDOMClassInfo.h',
     'nsIGlobalObject.h',
     'nsImageLoadingContent.h',
     'nsIMutationObserver.h',
     'nsINode.h',
     'nsINodeList.h',
     'nsIScriptContext.h',
     'nsIScriptGlobalObject.h',
     'nsIScriptObjectPrincipal.h',

--- a/dom/base/nsGlobalWindowInner.cpp
+++ b/dom/base/nsGlobalWindowInner.cpp
@@ -2843,19 +2843,17 @@ struct InterfaceShimEntry {
 
 // We add shims from Components.interfaces.nsIDOMFoo to window.Foo for each
 // interface that has interface constants that sites might be getting off
 // of Ci.
 const InterfaceShimEntry kInterfaceShimMap[] =
 { { "nsIXMLHttpRequest", "XMLHttpRequest" },
   { "nsIDOMDOMException", "DOMException" },
   { "nsIDOMNode", "Node" },
-  { "nsIDOMCSSPrimitiveValue", "CSSPrimitiveValue" },
   { "nsIDOMCSSRule", "CSSRule" },
-  { "nsIDOMCSSValue", "CSSValue" },
   { "nsIDOMEvent", "Event" },
   { "nsIDOMNSEvent", "Event" },
   { "nsIDOMKeyEvent", "KeyEvent" },
   { "nsIDOMMouseEvent", "MouseEvent" },
   { "nsIDOMMouseScrollEvent", "MouseScrollEvent" },
   { "nsIDOMMutationEvent", "MutationEvent" },
   { "nsIDOMUIEvent", "UIEvent" },
   { "nsIDOMHTMLMediaElement", "HTMLMediaElement" },

deleted file mode 100644
--- a/dom/base/nsIDOMClassInfo.h
+++ /dev/null
@@ -1,29 +0,0 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim: set ts=8 sts=2 et sw=2 tw=80: */
-/* 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/. */
-
-#ifndef nsIDOMClassInfo_h___
-#define nsIDOMClassInfo_h___
-
-#include "nsIXPCScriptable.h"
-
-#define DOM_BASE_SCRIPTABLE_FLAGS                                          \
-  (XPC_SCRIPTABLE_USE_JSSTUB_FOR_ADDPROPERTY |                             \
-   XPC_SCRIPTABLE_USE_JSSTUB_FOR_DELPROPERTY |                             \
-   XPC_SCRIPTABLE_ALLOW_PROP_MODS_TO_PROTOTYPE |                           \
-   XPC_SCRIPTABLE_DONT_ASK_INSTANCE_FOR_SCRIPTABLE |                       \
-   XPC_SCRIPTABLE_DONT_REFLECT_INTERFACE_NAMES)
-
-#define DEFAULT_SCRIPTABLE_FLAGS                                           \
-  (DOM_BASE_SCRIPTABLE_FLAGS |                                             \
-   XPC_SCRIPTABLE_WANT_RESOLVE |                                           \
-   XPC_SCRIPTABLE_WANT_PRECREATE)
-
-#define DOM_DEFAULT_SCRIPTABLE_FLAGS                                       \
-  (DEFAULT_SCRIPTABLE_FLAGS |                                              \
-   XPC_SCRIPTABLE_DONT_ENUM_QUERY_INTERFACE |                              \
-   XPC_SCRIPTABLE_CLASSINFO_INTERFACES_ONLY)
-
-#endif /* nsIDOMClassInfo_h___ */

--- a/dom/base/nsINode.h
+++ b/dom/base/nsINode.h
@@ -2135,22 +2135,16 @@ inline nsINode* NODE_FROM(C& aContent, D
 NS_DEFINE_STATIC_IID_ACCESSOR(nsINode, NS_INODE_IID)
 
 inline nsISupports*
 ToSupports(nsINode* aPointer)
 {
   return aPointer;
 }
 
-inline nsISupports*
-ToCanonicalSupports(nsINode* aPointer)
-{
-  return aPointer;
-}
-
 // Some checks are faster to do on nsIContent or Element than on
 // nsINode, so spit out FromNode versions taking those types too.
 #define NS_IMPL_FROMNODE_GENERIC(_class, _check, _const)                 \
   template<typename T>                                                   \
   static auto FromNode(_const T& aNode)                                  \
     -> decltype(static_cast<_const _class*>(&aNode))                     \
   {                                                                      \
     return aNode._check ? static_cast<_const _class*>(&aNode) : nullptr; \

--- a/dom/base/nsRange.h
+++ b/dom/base/nsRange.h
@@ -582,20 +582,14 @@ protected:
 
   bool mIsPositioned : 1;
   bool mMaySpanAnonymousSubtrees : 1;
   bool mIsGenerated : 1;
   bool mCalledByJS : 1;
 };
 
 inline nsISupports*
-ToCanonicalSupports(nsRange* aRange)
-{
-  return static_cast<nsIDOMRange*>(aRange);
-}
-
-inline nsISupports*
 ToSupports(nsRange* aRange)
 {
   return static_cast<nsIDOMRange*>(aRange);
 }
 
 #endif /* nsRange_h___ */

--- a/dom/battery/BatteryManager.cpp
+++ b/dom/battery/BatteryManager.cpp
@@ -8,17 +8,16 @@
 #include <limits>
 #include "BatteryManager.h"
 #include "Constants.h"
 #include "mozilla/DOMEventTargetHelper.h"
 #include "mozilla/Hal.h"
 #include "mozilla/dom/BatteryManagerBinding.h"
 #include "mozilla/Preferences.h"
 #include "nsContentUtils.h"
-#include "nsIDOMClassInfo.h"
 #include "nsIDocument.h"
 
 /**
  * We have to use macros here because our leak analysis tool things we are
  * leaking strings when we have |static const nsString|. Sad :(
  */
 #define LEVELCHANGE_EVENT_NAME           NS_LITERAL_STRING("levelchange")
 #define CHARGINGCHANGE_EVENT_NAME        NS_LITERAL_STRING("chargingchange")

--- a/dom/bindings/BindingUtils.h
+++ b/dom/bindings/BindingUtils.h
@@ -30,17 +30,17 @@
 #include "mozilla/Likely.h"
 #include "mozilla/MemoryReporting.h"
 #include "nsAutoPtr.h"
 #include "nsIDocument.h"
 #include "nsIGlobalObject.h"
 #include "nsIXPConnect.h"
 #include "nsJSUtils.h"
 #include "nsISupportsImpl.h"
-#include "qsObjectHelper.h"
+#include "xpcObjectHelper.h"
 #include "xpcpublic.h"
 #include "nsIVariant.h"
 #include "mozilla/dom/FakeString.h"
 
 #include "nsWrapperCacheInlines.h"
 
 class nsGenericHTMLElement;
 class nsIJSID;
@@ -1319,17 +1319,17 @@ template <class T>
 MOZ_ALWAYS_INLINE bool
 HandleNewBindingWrappingFailure(JSContext* cx, JS::Handle<JSObject*> scope,
                                 T* value, JS::MutableHandle<JS::Value> rval)
 {
   if (JS_IsExceptionPending(cx)) {
     return false;
   }
 
-  qsObjectHelper helper(value, GetWrapperCache(value));
+  xpcObjectHelper helper(value, GetWrapperCache(value));
   return NativeInterface2JSObjectAndThrowIfFailed(cx, scope, rval,
                                                   helper, nullptr, true);
 }
 
 // Helper for calling HandleNewBindingWrappingFailure with smart pointers
 // (nsAutoPtr/nsRefPtr/nsCOMPtr) or references.
 
 template <class T, bool isSmartPtr=IsSmartPtr<T>::value>
@@ -1553,17 +1553,17 @@ VariantToJsval(JSContext* aCx, nsIVarian
 // the nsWrapperCache for "p".
 template<class T>
 inline bool
 WrapObject(JSContext* cx, T* p, nsWrapperCache* cache, const nsIID* iid,
            JS::MutableHandle<JS::Value> rval)
 {
   if (xpc_FastGetCachedWrapper(cx, cache, rval))
     return true;
-  qsObjectHelper helper(p, cache);
+  xpcObjectHelper helper(ToSupports(p), cache);
   JS::Rooted<JSObject*> scope(cx, JS::CurrentGlobalOrNull(cx));
   return XPCOMObjectToJsval(cx, scope, helper, iid, true, rval);
 }
 
 // A specialization of the above for nsIVariant, because that needs to
 // do something different.
 template<>
 inline bool
@@ -1653,17 +1653,17 @@ WrapObject(JSContext* cx, JSObject& p, J
 // Given an object "p" that inherits from nsISupports, wrap it and return the
 // result.  Null is returned on wrapping failure.  This is somewhat similar to
 // WrapObject() above, but does NOT allow Xrays around the result, since we
 // don't want those for our parent object.
 template<typename T>
 static inline JSObject*
 WrapNativeISupports(JSContext* cx, T* p, nsWrapperCache* cache)
 {
-  qsObjectHelper helper(ToSupports(p), cache);
+  xpcObjectHelper helper(ToSupports(p), cache);
   JS::Rooted<JSObject*> scope(cx, JS::CurrentGlobalOrNull(cx));
   JS::Rooted<JS::Value> v(cx);
   return XPCOMObjectToJsval(cx, scope, helper, nullptr, false, &v) ?
          v.toObjectOrNull() :
          nullptr;
 }
 
 

--- a/dom/bindings/Bindings.conf
+++ b/dom/bindings/Bindings.conf
@@ -187,20 +187,16 @@ DOMInterfaces = {
     'concrete': False,
     'nativeType': 'mozilla::css::GroupRule',
 },
 
 'CSSLexer': {
     'wrapperCache': False
 },
 
-'CSSPrimitiveValue': {
-    'nativeType': 'nsROCSSPrimitiveValue',
-},
-
 'CSSRule': {
     'concrete': False,
     'nativeType': 'mozilla::css::Rule'
 },
 
 'CSSStyleDeclaration': {
     'nativeType': 'nsICSSDeclaration'
 },
@@ -209,24 +205,16 @@ DOMInterfaces = {
     'nativeType': 'mozilla::BindingStyleRule',
 },
 
 'CSSStyleSheet': {
     'nativeType': 'mozilla::StyleSheet',
     'binaryNames': { 'ownerRule': 'DOMOwnerRule' },
 },
 
-'CSSValue': {
-    'concrete': False
-},
-
-'CSSValueList': {
-    'nativeType': 'nsDOMCSSValueList'
-},
-
 'DedicatedWorkerGlobalScope': {
     'headerFile': 'mozilla/dom/WorkerScope.h',
 },
 
 'DeviceAcceleration': {
     'headerFile': 'mozilla/dom/DeviceMotionEvent.h',
 },
 
@@ -713,38 +701,30 @@ DOMInterfaces = {
 
 'Range': {
     'nativeType': 'nsRange',
     'binaryNames': {
         '__stringifier': 'ToString'
     }
 },
 
-'Rect': {
-    'nativeType': 'nsDOMCSSRect',
-},
-
 'Request': {
     'binaryNames': {
         'headers': 'headers_',
         'referrerPolicy': 'referrerPolicy_'
     },
     'implicitJSContext': [ 'arrayBuffer', 'blob', 'formData', 'json', 'text' ],
 },
 
 'Response': {
     'binaryNames': { 'headers': 'headers_' },
     'implicitJSContext': [ 'arrayBuffer', 'blob', 'formData', 'json', 'text',
                            'clone', 'cloneUnfiltered' ],
 },
 
-'RGBColor': {
-    'nativeType': 'nsDOMCSSRGBColor',
-},
-
 'RTCDataChannel': {
     'nativeType': 'nsDOMDataChannel',
 },
 
 'Screen': {
     'nativeType': 'nsScreen',
 },
 

--- a/dom/bindings/ToJSValue.h
+++ b/dom/bindings/ToJSValue.h
@@ -182,17 +182,17 @@ typename EnableIf<!IsBaseOf<nsWrapperCac
                   IsBaseOf<nsISupports, T>::value, bool>::Type
 ToJSValue(JSContext* aCx,
           T& aArgument,
           JS::MutableHandle<JS::Value> aValue)
 {
   // Make sure we're called in a compartment
   MOZ_ASSERT(JS::CurrentGlobalOrNull(aCx));
 
-  qsObjectHelper helper(ToSupports(&aArgument), nullptr);
+  xpcObjectHelper helper(ToSupports(&aArgument));
   JS::Rooted<JSObject*> scope(aCx, JS::CurrentGlobalOrNull(aCx));
   return XPCOMObjectToJsval(aCx, scope, helper, nullptr, true, aValue);
 }
 
 // Accept nsRefPtr/nsCOMPtr
 template <typename T>
 MOZ_MUST_USE bool
 ToJSValue(JSContext* aCx,

--- a/dom/clients/manager/ClientHandle.cpp
+++ b/dom/clients/manager/ClientHandle.cpp
@@ -44,24 +44,26 @@ ClientHandle::StartOp(const ClientOpCons
 {
   // Hold a ref to the client until the remote operation completes.  Otherwise
   // the ClientHandle might get de-refed and teardown the actor before we
   // get an answer.
   RefPtr<ClientHandle> kungFuGrip = this;
 
   MaybeExecute([aArgs, kungFuGrip, aRejectCallback,
                 resolve = Move(aResolveCallback)] (ClientHandleChild* aActor) {
+    MOZ_RELEASE_ASSERT(aActor);
     ClientHandleOpChild* actor =
       new ClientHandleOpChild(kungFuGrip, aArgs, Move(resolve),
                               Move(aRejectCallback));
     if (!aActor->SendPClientHandleOpConstructor(actor, aArgs)) {
       // Constructor failure will call reject callback via ActorDestroy()
       return;
     }
   }, [aRejectCallback] {
+    MOZ_RELEASE_ASSERT(aRejectCallback);
     aRejectCallback(NS_ERROR_DOM_INVALID_STATE_ERR);
   });
 }
 
 void
 ClientHandle::OnShutdownThing()
 {
   NS_ASSERT_OWNINGTHREAD(ClientHandle);

--- a/dom/clients/manager/ClientHandleOpChild.cpp
+++ b/dom/clients/manager/ClientHandleOpChild.cpp
@@ -34,15 +34,15 @@ ClientHandleOpChild::Recv__delete__(cons
 ClientHandleOpChild::ClientHandleOpChild(ClientHandle* aClientHandle,
                                          const ClientOpConstructorArgs& aArgs,
                                          const ClientOpCallback&& aResolveCallback,
                                          const ClientOpCallback&& aRejectCallback)
   : mClientHandle(aClientHandle)
   , mResolveCallback(Move(aResolveCallback))
   , mRejectCallback(Move(aRejectCallback))
 {
-  MOZ_DIAGNOSTIC_ASSERT(mClientHandle);
-  MOZ_DIAGNOSTIC_ASSERT(mResolveCallback);
-  MOZ_DIAGNOSTIC_ASSERT(mRejectCallback);
+  MOZ_RELEASE_ASSERT(mClientHandle);
+  MOZ_RELEASE_ASSERT(mResolveCallback);
+  MOZ_RELEASE_ASSERT(mRejectCallback);
 }
 
 } // namespace dom
 } // namespace mozilla

--- a/dom/clients/manager/ClientManager.cpp
+++ b/dom/clients/manager/ClientManager.cpp
@@ -22,18 +22,23 @@ namespace mozilla {
 namespace dom {
 
 using mozilla::ipc::BackgroundChild;
 using mozilla::ipc::PBackgroundChild;
 using mozilla::ipc::PrincipalInfo;
 
 namespace {
 
-uint32_t kBadThreadLocalIndex = -1;
+const uint32_t kBadThreadLocalIndex = -1;
+const uint32_t kThreadLocalMagic1 = 0x8d57eea6;
+const uint32_t kThreadLocalMagic2 = 0x59f375c9;
+uint32_t sClientManagerThreadLocalMagic1 = kThreadLocalMagic1;
 uint32_t sClientManagerThreadLocalIndex = kBadThreadLocalIndex;
+uint32_t sClientManagerThreadLocalMagic2 = kThreadLocalMagic2;
+uint32_t sClientManagerThreadLocalIndexDuplicate = kBadThreadLocalIndex;
 
 } // anonymous namespace
 
 ClientManager::ClientManager()
 {
   PBackgroundChild* parentActor = BackgroundChild::GetOrCreateForCurrentThread();
   if (NS_WARN_IF(!parentActor)) {
     Shutdown();
@@ -74,17 +79,21 @@ ClientManager::ClientManager()
 }
 
 ClientManager::~ClientManager()
 {
   NS_ASSERT_OWNINGTHREAD(ClientManager);
 
   Shutdown();
 
-  MOZ_DIAGNOSTIC_ASSERT(this == PR_GetThreadPrivate(sClientManagerThreadLocalIndex));
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalMagic1 == kThreadLocalMagic1);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalMagic2 == kThreadLocalMagic2);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalIndex != kBadThreadLocalIndex);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalIndex == sClientManagerThreadLocalIndexDuplicate);
+  MOZ_RELEASE_ASSERT(this == PR_GetThreadPrivate(sClientManagerThreadLocalIndex));
 
 #ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
   PRStatus status =
 #endif
     PR_SetThreadPrivate(sClientManagerThreadLocalIndex, nullptr);
   MOZ_DIAGNOSTIC_ASSERT(status == PR_SUCCESS);
 }
 
@@ -180,53 +189,65 @@ ClientManager::StartOp(const ClientOpCon
   RefPtr<ClientOpPromise> ref = promise.get();
   return ref.forget();
 }
 
 // static
 already_AddRefed<ClientManager>
 ClientManager::GetOrCreateForCurrentThread()
 {
-  MOZ_DIAGNOSTIC_ASSERT(sClientManagerThreadLocalIndex != kBadThreadLocalIndex);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalMagic1 == kThreadLocalMagic1);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalMagic2 == kThreadLocalMagic2);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalIndex != kBadThreadLocalIndex);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalIndex == sClientManagerThreadLocalIndexDuplicate);
   RefPtr<ClientManager> cm =
     static_cast<ClientManager*>(PR_GetThreadPrivate(sClientManagerThreadLocalIndex));
 
   if (!cm) {
     cm = new ClientManager();
 
 #ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
     PRStatus status =
 #endif
       PR_SetThreadPrivate(sClientManagerThreadLocalIndex, cm.get());
     MOZ_DIAGNOSTIC_ASSERT(status == PR_SUCCESS);
   }
 
-  MOZ_ASSERT(cm);
+  MOZ_RELEASE_ASSERT(cm);
   return cm.forget();
 }
 
 WorkerPrivate*
 ClientManager::GetWorkerPrivate() const
 {
   NS_ASSERT_OWNINGTHREAD(ClientManager);
   MOZ_DIAGNOSTIC_ASSERT(GetActor());
   return GetActor()->GetWorkerPrivate();
 }
 
 // static
 void
 ClientManager::Startup()
 {
   MOZ_ASSERT(NS_IsMainThread());
+
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalMagic1 == kThreadLocalMagic1);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalMagic2 == kThreadLocalMagic2);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalIndex == kBadThreadLocalIndex);
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalIndex == sClientManagerThreadLocalIndexDuplicate);
+
 #ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
   PRStatus status =
 #endif
     PR_NewThreadPrivateIndex(&sClientManagerThreadLocalIndex, nullptr);
   MOZ_DIAGNOSTIC_ASSERT(status == PR_SUCCESS);
 
+  MOZ_RELEASE_ASSERT(sClientManagerThreadLocalIndex != kBadThreadLocalIndex);
+  sClientManagerThreadLocalIndexDuplicate = sClientManagerThreadLocalIndex;
+
   ClientPrefsInit();
 }
 
 // static
 UniquePtr<ClientSource>
 ClientManager::CreateSource(ClientType aType, nsISerialEventTarget* aEventTarget,
                             nsIPrincipal* aPrincipal)
 {

--- a/dom/clients/manager/ClientThing.h
+++ b/dom/clients/manager/ClientThing.h
@@ -12,77 +12,99 @@ namespace mozilla {
 namespace dom {
 
 // Base class representing various Client "things" such as ClientHandle,
 // ClientSource, and ClientManager.  Currently it provides a common set
 // of code for handling activation and shutdown of IPC actors.
 template <typename ActorType>
 class ClientThing
 {
+  static const uint32_t kMagic1 = 0xC9FE2C9C;
+  static const uint32_t kMagic2 = 0x832072D4;
+
   ActorType* mActor;
+  uint32_t mMagic1;
+  uint32_t mMagic2;
   bool mShutdown;
 
 protected:
   ClientThing()
     : mActor(nullptr)
+    , mMagic1(kMagic1)
+    , mMagic2(kMagic2)
     , mShutdown(false)
   {
   }
 
   ~ClientThing()
   {
+    AssertIsValid();
     ShutdownThing();
+    mMagic1 = 0;
+    mMagic2 = 0;
+  }
+
+  void
+  AssertIsValid() const
+  {
+    MOZ_RELEASE_ASSERT(mMagic1 == kMagic1);
+    MOZ_RELEASE_ASSERT(mMagic2 == kMagic2);
   }
 
   // Return the current actor.
   ActorType*
   GetActor() const
   {
+    AssertIsValid();
     return mActor;
   }
 
   // Returns true if ShutdownThing() has been called.
   bool
   IsShutdown() const
   {
+    AssertIsValid();
     return mShutdown;
   }
 
   // Conditionally execute the given callable based on the current state.
   template<typename Callable>
   void
   MaybeExecute(const Callable& aSuccess,
                const std::function<void()>& aFailure = []{})
   {
+    AssertIsValid();
     if (mShutdown) {
       aFailure();
       return;
     }
     MOZ_DIAGNOSTIC_ASSERT(mActor);
     aSuccess(mActor);
   }
 
   // Attach activate the thing by attaching its underlying IPC actor.  This
   // will make the thing register as the actor's owner as well.  The actor
   // must call RevokeActor() to clear this weak back reference before its
   // destroyed.
   void
   ActivateThing(ActorType* aActor)
   {
+    AssertIsValid();
     MOZ_DIAGNOSTIC_ASSERT(aActor);
     MOZ_DIAGNOSTIC_ASSERT(!mActor);
     MOZ_DIAGNOSTIC_ASSERT(!mShutdown);
     mActor = aActor;
     mActor->SetOwner(this);
   }
 
   // Start destroying the underlying actor and disconnect the thing.
   void
   ShutdownThing()
   {
+    AssertIsValid();
     if (mShutdown) {
       return;
     }
     mShutdown = true;
 
     // If we are shutdown before the actor, then clear the weak references
     // between the actor and the thing.
     if (mActor) {
@@ -101,16 +123,17 @@ protected:
     // by default do nothing
   }
 
 public:
   // Clear the weak references between the thing and its IPC actor.
   void
   RevokeActor(ActorType* aActor)
   {
+    AssertIsValid();
     MOZ_DIAGNOSTIC_ASSERT(mActor);
     MOZ_DIAGNOSTIC_ASSERT(mActor == aActor);
     mActor->RevokeOwner(this);
     mActor = nullptr;
 
     // Also consider the ClientThing shutdown.  We simply set the flag
     // instead of calling ShutdownThing() to avoid calling MaybeStartTeardown()
     // on the destroyed actor.

--- a/dom/console/Console.cpp
+++ b/dom/console/Console.cpp
@@ -89,18 +89,18 @@ class ConsoleCallData final
 public:
   NS_INLINE_DECL_REFCOUNTING(ConsoleCallData)
 
   ConsoleCallData()
     : mMethodName(Console::MethodLog)
     , mTimeStamp(JS_Now() / PR_USEC_PER_MSEC)
     , mStartTimerValue(0)
     , mStartTimerStatus(Console::eTimerUnknown)
-    , mStopTimerDuration(0)
-    , mStopTimerStatus(Console::eTimerUnknown)
+    , mLogTimerDuration(0)
+    , mLogTimerStatus(Console::eTimerUnknown)
     , mCountValue(MAX_PAGE_COUNTERS)
     , mIDType(eUnknown)
     , mOuterIDNumber(0)
     , mInnerIDNumber(0)
     , mStatus(eUnused)
   {}
 
   bool
@@ -216,24 +216,24 @@ public:
   // They will be set on the owning thread and never touched again on that
   // thread. They will be used in order to create a ConsoleTimerStart dictionary
   // when console.time() is used.
   DOMHighResTimeStamp mStartTimerValue;
   nsString mStartTimerLabel;
   Console::TimerStatus mStartTimerStatus;
 
   // These values are set in the owning thread and they contain the duration,
-  // the name and the status of the StopTimer method. If status is false,
+  // the name and the status of the LogTimer method. If status is false,
   // something went wrong. They will be set on the owning thread and never
   // touched again on that thread. They will be used in order to create a
-  // ConsoleTimerEnd dictionary. This members are set when
-  // console.timeEnd() is called.
-  double mStopTimerDuration;
-  nsString mStopTimerLabel;
-  Console::TimerStatus mStopTimerStatus;
+  // ConsoleTimerLogOrEnd dictionary. This members are set when
+  // console.timeEnd() or console.timeLog() are called.
+  double mLogTimerDuration;
+  nsString mLogTimerLabel;
+  Console::TimerStatus mLogTimerStatus;
 
   // These 2 values are set by IncreaseCounter on the owning thread and they are
   // used CreateCounterValue. These members are set when console.count() is
   // called.
   nsString mCountLabel;
   uint32_t mCountValue;
 
   // The concept of outerID and innerID is misleading because when a
@@ -1226,40 +1226,52 @@ Console::GroupEnd(const GlobalObject& aG
 {
   const Sequence<JS::Value> data;
   Method(aGlobal, MethodGroupEnd, NS_LITERAL_STRING("groupEnd"), data);
 }
 
 /* static */ void
 Console::Time(const GlobalObject& aGlobal, const nsAString& aLabel)
 {
-  StringMethod(aGlobal, aLabel, MethodTime, NS_LITERAL_STRING("time"));
+  StringMethod(aGlobal, aLabel, Sequence<JS::Value>(), MethodTime,
+               NS_LITERAL_STRING("time"));
 }
 
 /* static */ void
 Console::TimeEnd(const GlobalObject& aGlobal, const nsAString& aLabel)
 {
-  StringMethod(aGlobal, aLabel, MethodTimeEnd, NS_LITERAL_STRING("timeEnd"));
+  StringMethod(aGlobal, aLabel, Sequence<JS::Value>(), MethodTimeEnd,
+               NS_LITERAL_STRING("timeEnd"));
+}
+
+/* static */ void
+Console::TimeLog(const GlobalObject& aGlobal, const nsAString& aLabel,
+                 const Sequence<JS::Value>& aData)
+{
+  StringMethod(aGlobal, aLabel, aData, MethodTimeLog,
+               NS_LITERAL_STRING("timeLog"));
 }
 
 /* static */ void
 Console::StringMethod(const GlobalObject& aGlobal, const nsAString& aLabel,
-                      MethodName aMethodName, const nsAString& aMethodString)
+                      const Sequence<JS::Value>& aData, MethodName aMethodName,
+                      const nsAString& aMethodString)
 {
   RefPtr<Console> console = GetConsole(aGlobal);
   if (!console) {
     return;
   }
 
-  console->StringMethodInternal(aGlobal.Context(), aLabel, aMethodName,
+  console->StringMethodInternal(aGlobal.Context(), aLabel, aData, aMethodName,
                                 aMethodString);
 }
 
 void
 Console::StringMethodInternal(JSContext* aCx, const nsAString& aLabel,
+                              const Sequence<JS::Value>& aData,
                               MethodName aMethodName,
                               const nsAString& aMethodString)
 {
   ConsoleCommon::ClearException ce(aCx);
 
   Sequence<JS::Value> data;
   SequenceRooter<JS::Value> rooter(aCx, &data);
 
@@ -1267,16 +1279,22 @@ Console::StringMethodInternal(JSContext*
   if (!dom::ToJSValue(aCx, aLabel, &value)) {
     return;
   }
 
   if (!data.AppendElement(value, fallible)) {
     return;
   }
 
+  for (uint32_t i = 0; i < aData.Length(); ++i) {
+    if (!data.AppendElement(aData[i], fallible)) {
+      return;
+    }
+  }
+
   MethodInternal(aCx, aMethodName, aMethodString, data);
 }
 
 /* static */ void
 Console::TimeStamp(const GlobalObject& aGlobal,
                    const JS::Handle<JS::Value> aData)
 {
   JSContext* cx = aGlobal.Context();
@@ -1417,17 +1435,18 @@ Console::Assert(const GlobalObject& aGlo
   if (!aCondition) {
     Method(aGlobal, MethodAssert, NS_LITERAL_STRING("assert"), aData);
   }
 }
 
 /* static */ void
 Console::Count(const GlobalObject& aGlobal, const nsAString& aLabel)
 {
-  StringMethod(aGlobal, aLabel, MethodCount, NS_LITERAL_STRING("count"));
+  StringMethod(aGlobal, aLabel, Sequence<JS::Value>(), MethodCount,
+               NS_LITERAL_STRING("count"));
 }
 
 namespace {
 
 void
 StackFrameToStackEntry(JSContext* aCx, nsIStackFrame* aStackFrame,
                        ConsoleStackEntry& aStackEntry)
 {
@@ -1568,36 +1587,46 @@ Console::MethodInternal(JSContext* aCx, 
     // nsIStackFrame is not threadsafe, so we need to snapshot it now,
     // before we post our runnable to the main thread.
     callData->mReifiedStack.emplace();
     ReifyStack(aCx, stack, *callData->mReifiedStack);
   }
 
   DOMHighResTimeStamp monotonicTimer;
 
-  // Monotonic timer for 'time' and 'timeEnd'
+  // Monotonic timer for 'time', 'timeLog' and 'timeEnd'
   if ((aMethodName == MethodTime ||
+       aMethodName == MethodTimeLog ||
        aMethodName == MethodTimeEnd ||
        aMethodName == MethodTimeStamp) &&
       !MonotonicTimer(aCx, aMethodName, aData, &monotonicTimer)) {
     return;
   }
 
   if (aMethodName == MethodTime && !aData.IsEmpty()) {
     callData->mStartTimerStatus = StartTimer(aCx, aData[0],
                                              monotonicTimer,
                                              callData->mStartTimerLabel,
                                              &callData->mStartTimerValue);
   }
 
   else if (aMethodName == MethodTimeEnd && !aData.IsEmpty()) {
-    callData->mStopTimerStatus = StopTimer(aCx, aData[0],
-                                           monotonicTimer,
-                                           callData->mStopTimerLabel,
-                                           &callData->mStopTimerDuration);
+    callData->mLogTimerStatus = LogTimer(aCx, aData[0],
+                                         monotonicTimer,
+                                         callData->mLogTimerLabel,
+                                         &callData->mLogTimerDuration,
+                                         true /* Cancel timer */);
+  }
+
+  else if (aMethodName == MethodTimeLog && !aData.IsEmpty()) {
+    callData->mLogTimerStatus = LogTimer(aCx, aData[0],
+                                         monotonicTimer,
+                                         callData->mLogTimerLabel,
+                                         &callData->mLogTimerDuration,
+                                         false /* Cancel timer */);
   }
 
   else if (aMethodName == MethodCount) {
     callData->mCountValue = IncreaseCounter(aCx, aData, callData->mCountLabel);
     if (!callData->mCountValue) {
       return;
     }
   }
@@ -1858,20 +1887,21 @@ Console::PopulateConsoleNotificationInTh
     }
   }
 
   else if (aData->mMethodName == MethodTime && !aArguments.IsEmpty()) {
     event.mTimer = CreateStartTimerValue(aCx, aData->mStartTimerLabel,
                                          aData->mStartTimerStatus);
   }
 
-  else if (aData->mMethodName == MethodTimeEnd && !aArguments.IsEmpty()) {
-    event.mTimer = CreateStopTimerValue(aCx, aData->mStopTimerLabel,
-                                        aData->mStopTimerDuration,
-                                        aData->mStopTimerStatus);
+  else if ((aData->mMethodName == MethodTimeEnd ||
+            aData->mMethodName == MethodTimeLog) && !aArguments.IsEmpty()) {
+    event.mTimer = CreateLogOrEndTimerValue(aCx, aData->mLogTimerLabel,
+                                            aData->mLogTimerDuration,
+                                            aData->mLogTimerStatus);
   }
 
   else if (aData->mMethodName == MethodCount) {
     event.mCounter = CreateCounterValue(aCx, aData->mCountLabel,
                                         aData->mCountValue);
   }
 
   JSAutoCompartment ac2(aCx, targetScope);
@@ -2316,20 +2346,21 @@ Console::CreateStartTimerValue(JSContext
   if (!ToJSValue(aCx, timer, &value)) {
     return JS::UndefinedValue();
   }
 
   return value;
 }
 
 Console::TimerStatus
-Console::StopTimer(JSContext* aCx, const JS::Value& aName,
-                   DOMHighResTimeStamp aTimestamp,
-                   nsAString& aTimerLabel,
-                   double* aTimerDuration)
+Console::LogTimer(JSContext* aCx, const JS::Value& aName,
+                  DOMHighResTimeStamp aTimestamp,
+                  nsAString& aTimerLabel,
+                  double* aTimerDuration,
+                  bool aCancelTimer)
 {
   AssertIsOnOwningThread();
   MOZ_ASSERT(aTimerDuration);
 
   *aTimerDuration = 0;
 
   JS::Rooted<JS::Value> name(aCx, aName);
   JS::Rooted<JSString*> jsString(aCx, JS::ToString(aCx, name));
@@ -2340,34 +2371,42 @@ Console::StopTimer(JSContext* aCx, const
   nsAutoJSString key;
   if (NS_WARN_IF(!key.init(aCx, jsString))) {
     return eTimerJSException;
   }
 
   aTimerLabel = key;
 
   DOMHighResTimeStamp value = 0;
-  if (!mTimerRegistry.Remove(key, &value)) {
-    NS_WARNING("mTimerRegistry entry not found");
-    return eTimerDoesntExist;
+
+  if (aCancelTimer) {
+    if (!mTimerRegistry.Remove(key, &value)) {
+      NS_WARNING("mTimerRegistry entry not found");
+      return eTimerDoesntExist;
+    }
+  } else {
+    if (!mTimerRegistry.Get(key, &value)) {
+      NS_WARNING("mTimerRegistry entry not found");
+      return eTimerDoesntExist;
+    }
   }
 
   *aTimerDuration = aTimestamp - value;
   return eTimerDone;
 }
 
 JS::Value
-Console::CreateStopTimerValue(JSContext* aCx, const nsAString& aLabel,
-                              double aDuration, TimerStatus aStatus) const
+Console::CreateLogOrEndTimerValue(JSContext* aCx, const nsAString& aLabel,
+                                  double aDuration, TimerStatus aStatus) const
 {
   if (aStatus != eTimerDone) {
     return CreateTimerError(aCx, aLabel, aStatus);
   }
 
-  RootedDictionary<ConsoleTimerEnd> timer(aCx);
+  RootedDictionary<ConsoleTimerLogOrEnd> timer(aCx);
   timer.mName = aLabel;
   timer.mDuration = aDuration;
 
   JS::Rooted<JS::Value> value(aCx);
   if (!ToJSValue(aCx, timer, &value)) {
     return JS::UndefinedValue();
   }
 
@@ -2991,16 +3030,17 @@ Console::WebIDLLogLevelToInteger(Console
 {
   switch (aLevel) {
     case ConsoleLogLevel::All: return 0;
     case ConsoleLogLevel::Debug: return 2;
     case ConsoleLogLevel::Log: return 3;
     case ConsoleLogLevel::Info: return 3;
     case ConsoleLogLevel::Clear: return 3;
     case ConsoleLogLevel::Trace: return 3;
+    case ConsoleLogLevel::TimeLog: return 3;
     case ConsoleLogLevel::TimeEnd: return 3;
     case ConsoleLogLevel::Time: return 3;
     case ConsoleLogLevel::Group: return 3;
     case ConsoleLogLevel::GroupEnd: return 3;
     case ConsoleLogLevel::Profile: return 3;
     case ConsoleLogLevel::ProfileEnd: return 3;
     case ConsoleLogLevel::Dir: return 3;
     case ConsoleLogLevel::Dirxml: return 3;
@@ -3028,16 +3068,17 @@ Console::InternalLogLevelToInteger(Metho
     case MethodTable: return 3;
     case MethodTrace: return 3;
     case MethodDir: return 3;
     case MethodDirxml: return 3;
     case MethodGroup: return 3;
     case MethodGroupCollapsed: return 3;
     case MethodGroupEnd: return 3;
     case MethodTime: return 3;
+    case MethodTimeLog: return 3;
     case MethodTimeEnd: return 3;
     case MethodTimeStamp: return 3;
     case MethodAssert: return 3;
     case MethodCount: return 3;
     case MethodClear: return 3;
     case MethodProfile: return 3;
     case MethodProfileEnd: return 3;
     default:

--- a/dom/console/Console.h
+++ b/dom/console/Console.h
@@ -92,16 +92,20 @@ public:
 
   static void
   GroupEnd(const GlobalObject& aGlobal);
 
   static void
   Time(const GlobalObject& aGlobal, const nsAString& aLabel);
 
   static void
+  TimeLog(const GlobalObject& aGlobal, const nsAString& aLabel,
+          const Sequence<JS::Value>& aData);
+
+  static void
   TimeEnd(const GlobalObject& aGlobal, const nsAString& aLabel);
 
   static void
   TimeStamp(const GlobalObject& aGlobal, const JS::Handle<JS::Value> aData);
 
   static void
   Profile(const GlobalObject& aGlobal, const Sequence<JS::Value>& aData);
 
@@ -154,16 +158,17 @@ private:
     MethodTable,
     MethodTrace,
     MethodDir,
     MethodDirxml,
     MethodGroup,
     MethodGroupCollapsed,
     MethodGroupEnd,
     MethodTime,
+    MethodTimeLog,
     MethodTimeEnd,
     MethodTimeStamp,
     MethodAssert,
     MethodCount,
     MethodClear,
     MethodProfile,
     MethodProfileEnd,
   };
@@ -188,20 +193,22 @@ private:
          const nsAString& aString, const Sequence<JS::Value>& aData);
 
   void
   MethodInternal(JSContext* aCx, MethodName aName,
                  const nsAString& aString, const Sequence<JS::Value>& aData);
 
   static void
   StringMethod(const GlobalObject& aGlobal, const nsAString& aLabel,
-               MethodName aMethodName, const nsAString& aMethodString);
+               const Sequence<JS::Value>& aData, MethodName aMethodName,
+               const nsAString& aMethodString);
 
   void
   StringMethodInternal(JSContext* aCx, const nsAString& aLabel,
+                       const Sequence<JS::Value>& aData,
                        MethodName aMethodName, const nsAString& aMethodString);
 
   // This method must receive aCx and aArguments in the same JSCompartment.
   void
   ProcessCallData(JSContext* aCx,
                   ConsoleCallData* aData,
                   const Sequence<JS::Value>& aArguments);
 
@@ -312,43 +319,45 @@ private:
   // thread.
   // * aCx - this is the context that will root the returned value.
   // * aTimerLabel - this label must be what StartTimer received as aTimerLabel.
   // * aTimerStatus - the return value of StartTimer.
   JS::Value
   CreateStartTimerValue(JSContext* aCx, const nsAString& aTimerLabel,
                         TimerStatus aTimerStatus) const;
 
-  // StopTimer follows the same pattern as StartTimer: it runs on the
+  // LogTimer follows the same pattern as StartTimer: it runs on the
   // owning thread and populates aTimerLabel and aTimerDuration, used by
-  // CreateStopTimerValue.
+  // CreateLogOrEndTimerValue.
   // * aCx - the JSContext rooting aName.
   // * aName - this is (should be) the name of the timer as JS::Value.
   // * aTimestamp - the monotonicTimer for this context taken from
   //                performance.now().
   // * aTimerLabel - This label will be populated with the aName converted to a
   //                 string.
   // * aTimerDuration - the difference between aTimestamp and when the timer
   //                    started (see StartTimer).
+  // * aCancelTimer - if true, the timer is removed from the table.
   TimerStatus
-  StopTimer(JSContext* aCx, const JS::Value& aName,
-            DOMHighResTimeStamp aTimestamp,
-            nsAString& aTimerLabel,
-            double* aTimerDuration);
+  LogTimer(JSContext* aCx, const JS::Value& aName,
+           DOMHighResTimeStamp aTimestamp,
+           nsAString& aTimerLabel,
+           double* aTimerDuration,
+           bool aCancelTimer);
 
   // This method generates a ConsoleTimerEnd dictionary exposed as JS::Value, or
-  // a ConsoleTimerError dictionary if aTimerStatus is false. See StopTimer.
+  // a ConsoleTimerError dictionary if aTimerStatus is false. See LogTimer.
   // * aCx - this is the context that will root the returned value.
-  // * aTimerLabel - this label must be what StopTimer received as aTimerLabel.
-  // * aTimerDuration - this is what StopTimer received as aTimerDuration
-  // * aTimerStatus - the return value of StopTimer.
+  // * aTimerLabel - this label must be what LogTimer received as aTimerLabel.
+  // * aTimerDuration - this is what LogTimer received as aTimerDuration
+  // * aTimerStatus - the return value of LogTimer.
   JS::Value
-  CreateStopTimerValue(JSContext* aCx, const nsAString& aTimerLabel,
-                       double aTimerDuration,
-                       TimerStatus aTimerStatus) const;
+  CreateLogOrEndTimerValue(JSContext* aCx, const nsAString& aTimerLabel,
+                           double aTimerDuration,
+                           TimerStatus aTimerStatus) const;
 
   // The method populates a Sequence from an array of JS::Value.
   bool
   ArgumentsToValueList(const Sequence<JS::Value>& aData,
                        Sequence<JS::Value>& aSequence) const;
 
   // This method follows the same pattern as StartTimer: its runs on the owning
   // thread and populate aCountLabel, used by CreateCounterValue. Returns

--- a/dom/console/ConsoleInstance.cpp
+++ b/dom/console/ConsoleInstance.cpp
@@ -142,24 +142,34 @@ ConsoleInstance::GroupEnd(JSContext* aCx
   const Sequence<JS::Value> data;
   mConsole->MethodInternal(aCx, Console::MethodGroupEnd,
                            NS_LITERAL_STRING("groupEnd"), data);
 }
 
 void
 ConsoleInstance::Time(JSContext* aCx, const nsAString& aLabel)
 {
-  mConsole->StringMethodInternal(aCx, aLabel, Console::MethodTime,
+  mConsole->StringMethodInternal(aCx, aLabel, Sequence<JS::Value>(),
+                                 Console::MethodTime,
                                  NS_LITERAL_STRING("time"));
 }
 
 void
+ConsoleInstance::TimeLog(JSContext* aCx, const nsAString& aLabel,
+                         const Sequence<JS::Value>& aData)
+{
+  mConsole->StringMethodInternal(aCx, aLabel, aData, Console::MethodTimeLog,
+                                 NS_LITERAL_STRING("timeLog"));
+}
+
+void
 ConsoleInstance::TimeEnd(JSContext* aCx, const nsAString& aLabel)
 {
-  mConsole->StringMethodInternal(aCx, aLabel, Console::MethodTimeEnd,
+  mConsole->StringMethodInternal(aCx, aLabel, Sequence<JS::Value>(),
+                                 Console::MethodTimeEnd,
                                  NS_LITERAL_STRING("timeEnd"));
 }
 
 void
 ConsoleInstance::TimeStamp(JSContext* aCx, const JS::Handle<JS::Value> aData)
 {
   ConsoleCommon::ClearException ce(aCx);
 
@@ -196,17 +206,18 @@ ConsoleInstance::Assert(JSContext* aCx, 
     mConsole->MethodInternal(aCx, Console::MethodAssert,
                              NS_LITERAL_STRING("assert"), aData);
   }
 }
 
 void
 ConsoleInstance::Count(JSContext* aCx, const nsAString& aLabel)
 {
-  mConsole->StringMethodInternal(aCx, aLabel, Console::MethodCount,
+  mConsole->StringMethodInternal(aCx, aLabel, Sequence<JS::Value>(),
+                                 Console::MethodCount,
                                  NS_LITERAL_STRING("count"));
 }
 
 void
 ConsoleInstance::Clear(JSContext* aCx)
 {
   const Sequence<JS::Value> data;
   mConsole->MethodInternal(aCx, Console::MethodClear,

--- a/dom/console/ConsoleInstance.h
+++ b/dom/console/ConsoleInstance.h
@@ -70,16 +70,20 @@ public:
 
   void
   GroupEnd(JSContext* aCx);
 
   void
   Time(JSContext* aCx, const nsAString& aLabel);
 
   void
+  TimeLog(JSContext* aCx, const nsAString& aLabel,
+          const Sequence<JS::Value>& aData);
+
+  void
   TimeEnd(JSContext* aCx, const nsAString& aLabel);
 
   void
   TimeStamp(JSContext* aCx, const JS::Handle<JS::Value> aData);
 
   void
   Profile(JSContext* aCx, const Sequence<JS::Value>& aData);
 

--- a/dom/console/tests/mochitest.ini
+++ b/dom/console/tests/mochitest.ini
@@ -5,8 +5,9 @@ support-files =
 [test_bug659625.html]
 [test_bug978522.html]
 [test_bug979109.html]
 [test_bug989665.html]
 [test_consoleEmptyStack.html]
 [test_console_binding.html]
 [test_console_proto.html]
 [test_devtools_pref.html]
+[test_timer.html]

new file mode 100644
--- /dev/null
+++ b/dom/console/tests/test_timer.html
@@ -0,0 +1,111 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for timeStart/timeLog/timeEnd in console</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+  <script type="application/javascript">
+
+SimpleTest.waitForExplicitFinish();
+
+function ConsoleListener() {
+  SpecialPowers.addObserver(this, "console-api-log-event");
+}
+
+ConsoleListener.prototype = {
+  observe(aSubject, aTopic, aData) {
+    let obj = aSubject.wrappedJSObject;
+    if (obj.arguments[0] != 'test') {
+      return;
+    }
+
+    if (!this._cb) {
+      ok(false, "Callback not set!");
+      return;
+    }
+
+    if (!this._cb(obj)) {
+      return;
+    }
+
+    this._cb = null;
+    this._resolve();
+  },
+
+  shutdown() {
+    SpecialPowers.removeObserver(this, "console-api-log-event");
+  },
+
+  waitFor(cb) {
+    return new Promise(resolve => {
+      this._cb = cb;
+      this._resolve = resolve;
+    });
+  },
+};
+
+let listener = new ConsoleListener();
+
+// Timer creation:
+async function runTest() {
+  let cl = listener.waitFor(obj => {
+    return ("timer" in obj) &&
+           ("name" in obj.timer) &&
+           obj.timer.name == 'test';
+  });
+
+  console.time('test');
+  await cl;
+  ok(true, "Console.time received!");
+
+  // Timer check:
+  cl = listener.waitFor(obj => {
+    return ("timer" in obj) &&
+           ("name" in obj.timer) &&
+           obj.timer.name == 'test' &&
+           ("duration" in obj.timer) &&
+           obj.timer.duration > 0 &&
+           obj.arguments[1] == 1 &&
+           obj.arguments[2] == 2 &&
+           obj.arguments[3] == 3 &&
+           obj.arguments[4] == 4;
+  });
+  console.timeLog('test', 1, 2, 3, 4);
+  await cl;
+  ok(true, "Console.timeLog received!");
+
+  // Time deleted:
+  cl = listener.waitFor(obj => {
+    return ("timer" in obj) &&
+           ("name" in obj.timer) &&
+           obj.timer.name == 'test' &&
+           ("duration" in obj.timer) &&
+           obj.timer.duration > 0;
+  });
+  console.timeEnd('test');
+  await cl;
+  ok(true, "Console.timeEnd received!");
+
+  // Here an error:
+  cl = listener.waitFor(obj => {
+    return ("timer" in obj) &&
+           ("name" in obj.timer) &&
+           obj.timer.name == 'test' &&
+           ("error" in obj.timer);
+  });
+  console.timeLog('test');
+  await cl;
+  ok(true, "Console.time with error received!");
+}
+
+runTest().then(() => {
+  listener.shutdown();
+  SimpleTest.finish();
+});
+
+  </script>
+</body>
+</html>

--- a/dom/events/EventStateManager.cpp
+++ b/dom/events/EventStateManager.cpp
@@ -5364,16 +5364,64 @@ EventStateManager::ResetLastOverForConte
   if (aElemWrapper && aElemWrapper->mLastOverElement &&
       nsContentUtils::ContentIsDescendantOf(aElemWrapper->mLastOverElement,
                                             aContent)) {
     aElemWrapper->mLastOverElement = nullptr;
   }
 }
 
 void
+EventStateManager::RemoveNodeFromChainIfNeeded(EventStates aState,
+                                               nsIContent* aContentRemoved,
+                                               bool aNotify)
+{
+  MOZ_ASSERT(aState == NS_EVENT_STATE_HOVER || aState == NS_EVENT_STATE_ACTIVE);
+  if (!aContentRemoved->IsElement() ||
+      !aContentRemoved->AsElement()->State().HasState(aState)) {
+    return;
+  }
+
+  nsCOMPtr<nsIContent>& leaf =
+    aState == NS_EVENT_STATE_HOVER ? mHoverContent : mActiveContent;
+
+  MOZ_ASSERT(leaf);
+  // XBL Likes to unbind content without notifying, thus the
+  // NODE_IS_ANONYMOUS_ROOT check...
+  MOZ_ASSERT(nsContentUtils::ContentIsFlattenedTreeDescendantOf(
+               leaf, aContentRemoved) ||
+             leaf->SubtreeRoot()->HasFlag(NODE_IS_ANONYMOUS_ROOT));
+
+  nsIContent* newLeaf = aContentRemoved->GetFlattenedTreeParent();
+  MOZ_ASSERT_IF(newLeaf,
+                newLeaf->IsElement() &&
+                newLeaf->AsElement()->State().HasState(aState));
+  if (aNotify) {
+    SetContentState(newLeaf, aState);
+  } else {
+    // We don't update the removed content's state here, since removing NAC
+    // happens from layout and we don't really want to notify at that point or
+    // what not.
+    //
+    // Also, NAC is not observable and NAC being removed will go away soon.
+    leaf = newLeaf;
+  }
+  MOZ_ASSERT(leaf == newLeaf);
+}
+
+void
+EventStateManager::NativeAnonymousContentRemoved(nsIContent* aContent)
+{
+  // FIXME(bug 1450250): <svg:use> is nasty.
+  MOZ_ASSERT(aContent->IsRootOfNativeAnonymousSubtree() ||
+             aContent->GetParentNode()->IsSVGElement(nsGkAtoms::use));
+  RemoveNodeFromChainIfNeeded(NS_EVENT_STATE_HOVER, aContent, false);
+  RemoveNodeFromChainIfNeeded(NS_EVENT_STATE_ACTIVE, aContent, false);
+}
+
+void
 EventStateManager::ContentRemoved(nsIDocument* aDocument, nsIContent* aContent)
 {
   /*
    * Anchor and area elements when focused or hovered might make the UI to show
    * the current link. We want to make sure that the UI gets informed when they
    * are actually removed from the DOM.
    */
   if (aContent->IsAnyOfHTMLElements(nsGkAtoms::a, nsGkAtoms::area) &&
@@ -5387,29 +5435,18 @@ EventStateManager::ContentRemoved(nsIDoc
   IMEStateManager::OnRemoveContent(mPresContext, aContent);
 
   // inform the focus manager that the content is being removed. If this
   // content is focused, the focus will be removed without firing events.
   nsFocusManager* fm = nsFocusManager::GetFocusManager();
   if (fm)
     fm->ContentRemoved(aDocument, aContent);
 
-  if (mHoverContent &&
-      nsContentUtils::ContentIsFlattenedTreeDescendantOf(mHoverContent, aContent)) {
-    // Since hover is hierarchical, set the current hover to the
-    // content's parent node.
-    SetContentState(aContent->GetFlattenedTreeParent(), NS_EVENT_STATE_HOVER);
-  }
-
-  if (mActiveContent &&
-      nsContentUtils::ContentIsFlattenedTreeDescendantOf(mActiveContent, aContent)) {
-    // Active is hierarchical, so set the current active to the
-    // content's parent node.
-    SetContentState(aContent->GetFlattenedTreeParent(), NS_EVENT_STATE_ACTIVE);
-  }
+  RemoveNodeFromChainIfNeeded(NS_EVENT_STATE_HOVER, aContent, true);
+  RemoveNodeFromChainIfNeeded(NS_EVENT_STATE_ACTIVE, aContent, true);
 
   if (sDragOverContent &&
       sDragOverContent->OwnerDoc() == aContent->OwnerDoc() &&
       nsContentUtils::ContentIsFlattenedTreeDescendantOf(sDragOverContent, aContent)) {
     sDragOverContent = nullptr;
   }
 
   PointerEventHandler::ReleaseIfCaptureByDescendant(aContent);

--- a/dom/events/EventStateManager.h
+++ b/dom/events/EventStateManager.h
@@ -143,16 +143,18 @@ public:
    * @return  Whether the content was able to change all states. Returns false
    *                  if a resulting DOM event causes the content node passed in
    *                  to not change states. Note, the frame for the content may
    *                  change as a result of the content state change, because of
    *                  frame reconstructions that may occur, but this does not
    *                  affect the return value.
    */
   bool SetContentState(nsIContent* aContent, EventStates aState);
+
+  void NativeAnonymousContentRemoved(nsIContent* aAnonContent);
   void ContentRemoved(nsIDocument* aDocument, nsIContent* aContent);
 
   bool EventStatusOK(WidgetGUIEvent* aEvent);
 
   /**
    * EventStateManager stores IMEContentObserver while it's observing contents.
    * Following mehtods are called by IMEContentObserver when it starts to
    * observe or stops observing the content.
@@ -1082,16 +1084,24 @@ protected:
   bool HandleCrossProcessEvent(WidgetEvent* aEvent,
                                nsEventStatus* aStatus);
 
   void ReleaseCurrentIMEContentObserver();
 
   void HandleQueryContentEvent(WidgetQueryContentEvent* aEvent);
 
 private:
+  // Removes a node from the :hover / :active chain if needed, notifying if the
+  // node is not a NAC subtree.
+  //
+  // Only meant to be called from ContentRemoved and
+  // NativeAnonymousContentRemoved.
+  void RemoveNodeFromChainIfNeeded(EventStates aState,
+                                   nsIContent* aContentRemoved,
+                                   bool aNotify);
 
   bool IsEventOutsideDragThreshold(WidgetInputEvent* aEvent) const;
 
   static inline void DoStateChange(dom::Element* aElement,
                                    EventStates aState, bool aAddState);
   static inline void DoStateChange(nsIContent* aContent, EventStates aState,
                                    bool aAddState);
   static void UpdateAncestorState(nsIContent* aStartNode,

--- a/dom/html/nsGenericHTMLElement.h
+++ b/dom/html/nsGenericHTMLElement.h
@@ -1341,21 +1341,9 @@ NS_DECLARE_NS_NEW_HTML_ELEMENT(TextArea)
 NS_DECLARE_NS_NEW_HTML_ELEMENT(Tfoot)
 NS_DECLARE_NS_NEW_HTML_ELEMENT(Thead)
 NS_DECLARE_NS_NEW_HTML_ELEMENT(Time)
 NS_DECLARE_NS_NEW_HTML_ELEMENT(Title)
 NS_DECLARE_NS_NEW_HTML_ELEMENT(Track)
 NS_DECLARE_NS_NEW_HTML_ELEMENT(Unknown)
 NS_DECLARE_NS_NEW_HTML_ELEMENT(Video)
 
-inline nsISupports*
-ToSupports(nsGenericHTMLElement* aHTMLElement)
-{
-  return static_cast<nsIContent*>(aHTMLElement);
-}
-
-inline nsISupports*
-ToCanonicalSupports(nsGenericHTMLElement* aHTMLElement)
-{
-  return static_cast<nsIContent*>(aHTMLElement);
-}
-
 #endif /* nsGenericHTMLElement_h___ */

--- a/dom/html/nsHTMLDocument.cpp
+++ b/dom/html/nsHTMLDocument.cpp
@@ -1884,74 +1884,59 @@ nsHTMLDocument::CaptureEvents()
 }
 
 void
 nsHTMLDocument::ReleaseEvents()
 {
   WarnOnceAbout(nsIDocument::eUseOfReleaseEvents);
 }
 
-nsISupports*
-nsHTMLDocument::ResolveName(const nsAString& aName, nsWrapperCache **aCache)
+bool
+nsHTMLDocument::ResolveName(JSContext* aCx, const nsAString& aName,
+                            JS::MutableHandle<JS::Value> aRetval, ErrorResult& aError)
 {
   nsIdentifierMapEntry *entry = mIdentifierMap.GetEntry(aName);
   if (!entry) {
-    *aCache = nullptr;
-    return nullptr;
+    return false;
   }
 
   nsBaseContentList *list = entry->GetNameContentList();
   uint32_t length = list ? list->Length() : 0;
 
+  nsIContent *node;
   if (length > 0) {
-    if (length == 1) {
-      // Only one element in the list, return the element instead of returning
-      // the list.
-      nsIContent *node = list->Item(0);
-      *aCache = node;
-      return node;
+    if (length > 1) {
+      // The list contains more than one element, return the whole list.
+      if (!ToJSValue(aCx, list, aRetval)) {
+        aError.NoteJSContextException(aCx);
+        return false;
+      }
+      return true;
     }
 
-    // The list contains more than one element, return the whole list.
-    *aCache = list;
-    return list;
-  }
-
-  // No named items were found, see if there's one registerd by id for aName.
-  Element *e = entry->GetIdElement();
-
-  if (e && nsGenericHTMLElement::ShouldExposeIdAsHTMLDocumentProperty(e)) {
-    *aCache = e;
-    return e;
+    // Only one element in the list, return the element instead of returning
+    // the list.
+    node = list->Item(0);
+  } else {
+    // No named items were found, see if there's one registerd by id for aName.
+    Element *e = entry->GetIdElement();
+  
+    if (!e || !nsGenericHTMLElement::ShouldExposeIdAsHTMLDocumentProperty(e)) {
+      return false;
+    }
+
+    node = e;
   }
 
-  *aCache = nullptr;
-  return nullptr;
-}
-
-void
-nsHTMLDocument::NamedGetter(JSContext* cx, const nsAString& aName, bool& aFound,
-                            JS::MutableHandle<JSObject*> aRetval,
-                            ErrorResult& rv)
-{
-  nsWrapperCache* cache;
-  nsISupports* supp = ResolveName(aName, &cache);
-  if (!supp) {
-    aFound = false;
-    aRetval.set(nullptr);
-    return;
+  if (!ToJSValue(aCx, node, aRetval)) {
+    aError.NoteJSContextException(aCx);
+    return false;
   }
 
-  JS::Rooted<JS::Value> val(cx);
-  if (!dom::WrapObject(cx, supp, cache, nullptr, &val)) {
-    rv.Throw(NS_ERROR_OUT_OF_MEMORY);
-    return;
-  }
-  aFound = true;
-  aRetval.set(&val.toObject());
+  return true;
 }
 
 void
 nsHTMLDocument::GetSupportedNames(nsTArray<nsString>& aNames)
 {
   for (auto iter = mIdentifierMap.Iter(); !iter.Done(); iter.Next()) {
     nsIdentifierMapEntry* entry = iter.Get();
     if (entry->HasNameElement() ||

--- a/dom/html/nsHTMLDocument.h
+++ b/dom/html/nsHTMLDocument.h
@@ -74,17 +74,19 @@ public:
 
   nsContentList* GetExistingForms() const
   {
     return mForms;
   }
 
   mozilla::dom::HTMLAllCollection* All();
 
-  nsISupports* ResolveName(const nsAString& aName, nsWrapperCache **aCache);
+  // Returns whether an object was found for aName.
+  bool ResolveName(JSContext* aCx, const nsAString& aName,
+                   JS::MutableHandle<JS::Value> aRetval, mozilla::ErrorResult& aError);
 
   virtual void AddedForm() override;
   virtual void RemovedForm() override;
   virtual int32_t GetNumFormsSynchronous() override;
   virtual void TearingDownEditor() override;
   virtual void SetIsXHTML(bool aXHTML) override
   {
     mType = (aXHTML ? eXHTML : eHTML);
@@ -146,17 +148,23 @@ public:
   void GetDomain(nsAString& aDomain);
   void SetDomain(const nsAString& aDomain, mozilla::ErrorResult& rv);
   bool IsRegistrableDomainSuffixOfOrEqualTo(const nsAString& aHostSuffixString,
                                             const nsACString& aOrigHost);
   void GetCookie(nsAString& aCookie, mozilla::ErrorResult& rv);
   void SetCookie(const nsAString& aCookie, mozilla::ErrorResult& rv);
   void NamedGetter(JSContext* cx, const nsAString& aName, bool& aFound,
                    JS::MutableHandle<JSObject*> aRetval,
-                   mozilla::ErrorResult& rv);
+                   mozilla::ErrorResult& rv)
+  {
+    JS::Rooted<JS::Value> v(cx);
+    if ((aFound = ResolveName(cx, aName, &v, rv))) {
+      aRetval.set(v.toObjectOrNull());
+    }
+  }
   void GetSupportedNames(nsTArray<nsString>& aNames);
   already_AddRefed<nsIDocument> Open(JSContext* cx,
                                      const mozilla::dom::Optional<nsAString>& /* unused */,
                                      const nsAString& aReplace,
                                      mozilla::ErrorResult& aError);
   already_AddRefed<nsPIDOMWindowOuter>
   Open(JSContext* cx,
        const nsAString& aURL,

--- a/dom/network/Connection.cpp
+++ b/dom/network/Connection.cpp
@@ -2,17 +2,16 @@
 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
 /* 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/. */
 
 #include "Connection.h"
 #include "ConnectionMainThread.h"
 #include "ConnectionWorker.h"
-#include "nsIDOMClassInfo.h"
 #include "Constants.h"
 #include "mozilla/Telemetry.h"
 #include "mozilla/dom/WorkerPrivate.h"
 
 /**
  * We have to use macros here because our leak analysis tool things we are
  * leaking strings when we have |static const nsString|. Sad :(
  */

--- a/dom/serviceworkers/ServiceWorker.cpp
+++ b/dom/serviceworkers/ServiceWorker.cpp
@@ -3,16 +3,17 @@
 /* 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/. */
 
 #include "ServiceWorker.h"
 
 #include "nsIDocument.h"
 #include "nsPIDOMWindow.h"
+#include "ServiceWorkerImpl.h"
 #include "ServiceWorkerManager.h"
 #include "ServiceWorkerPrivate.h"
 
 #include "mozilla/dom/DOMPrefs.h"
 #include "mozilla/dom/ClientIPCTypes.h"
 #include "mozilla/dom/ClientState.h"
 #include "mozilla/dom/Promise.h"
 #include "mozilla/dom/ServiceWorkerGlobalScopeBinding.h"
@@ -57,17 +58,18 @@ ServiceWorker::Create(nsIGlobalObject* a
     return ref.forget();
   }
 
   RefPtr<ServiceWorkerInfo> info = reg->GetByDescriptor(aDescriptor);
   if (!info) {
     return ref.forget();
   }
 
-  ref = new ServiceWorker(aOwner, aDescriptor, info);
+  RefPtr<ServiceWorker::Inner> inner = new ServiceWorkerImpl(info);
+  ref = new ServiceWorker(aOwner, aDescriptor, inner);
   return ref.forget();
 }
 
 ServiceWorker::ServiceWorker(nsIGlobalObject* aGlobal,
                              const ServiceWorkerDescriptor& aDescriptor,
                              ServiceWorker::Inner* aInner)
   : DOMEventTargetHelper(aGlobal)
   , mDescriptor(aDescriptor)

new file mode 100644
--- /dev/null
+++ b/dom/serviceworkers/ServiceWorkerImpl.cpp
@@ -0,0 +1,65 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#include "ServiceWorkerImpl.h"
+
+namespace mozilla {
+namespace dom {
+
+ServiceWorkerImpl::~ServiceWorkerImpl()
+{
+  MOZ_DIAGNOSTIC_ASSERT(!mOuter);
+  mInfo->RemoveListener(this);
+}
+
+void
+ServiceWorkerImpl::AddServiceWorker(ServiceWorker* aWorker)
+{
+  MOZ_DIAGNOSTIC_ASSERT(!mOuter);
+  MOZ_DIAGNOSTIC_ASSERT(aWorker);
+  mOuter = aWorker;
+
+  // Wait to attach to the info as a listener until we have the outer
+  // set.  This is important because the info will try to set the
+  // state immediately.
+  mInfo->AddListener(this);
+}
+
+void
+ServiceWorkerImpl::RemoveServiceWorker(ServiceWorker* aWorker)
+{
+  MOZ_DIAGNOSTIC_ASSERT(mOuter);
+  MOZ_DIAGNOSTIC_ASSERT(mOuter == aWorker);
+  mOuter = nullptr;
+}
+
+void
+ServiceWorkerImpl::PostMessage(ipc::StructuredCloneData&& aData,
+                               const ClientInfo& aClientInfo,
+                               const ClientState& aClientState)
+{
+  mInfo->PostMessage(Move(aData), aClientInfo, aClientState);
+}
+
+void
+ServiceWorkerImpl::SetState(ServiceWorkerState aState)
+{
+  if (!mOuter) {
+    return;
+  }
+  mOuter->SetState(aState);
+}
+
+
+ServiceWorkerImpl::ServiceWorkerImpl(ServiceWorkerInfo* aInfo)
+  : mInfo(aInfo)
+  , mOuter(nullptr)
+{
+  MOZ_DIAGNOSTIC_ASSERT(mInfo);
+}
+
+} // namespace dom
+} // namespace mozilla

new file mode 100644
--- /dev/null
+++ b/dom/serviceworkers/ServiceWorkerImpl.h
@@ -0,0 +1,51 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_dom_ServiceWorkerImpl_h
+#define mozilla_dom_ServiceWorkerImpl_h
+
+#include "ServiceWorker.h"
+#include "ServiceWorkerInfo.h"
+
+namespace mozilla {
+namespace dom {
+
+class ServiceWorkerInfo;
+
+class ServiceWorkerImpl final : public ServiceWorker::Inner
+                              , public ServiceWorkerInfo::Listener
+{
+  RefPtr<ServiceWorkerInfo> mInfo;
+  ServiceWorker* mOuter;
+
+  ~ServiceWorkerImpl();
+
+  // ServiceWorker::Inner interface
+  void
+  AddServiceWorker(ServiceWorker* aWorker) override;
+
+  void
+  RemoveServiceWorker(ServiceWorker* aWorker) override;
+
+  void
+  PostMessage(ipc::StructuredCloneData&& aData,
+              const ClientInfo& aClientInfo,
+              const ClientState& aClientState) override;
+
+  // ServiceWorkerInfo::Listener interface
+  void
+  SetState(ServiceWorkerState aState) override;
+
+public:
+  explicit ServiceWorkerImpl(ServiceWorkerInfo* aInfo);
+
+  NS_INLINE_DECL_REFCOUNTING(ServiceWorkerImpl, override);
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_dom_ServiceWorkerImpl_h

--- a/dom/serviceworkers/ServiceWorkerInfo.cpp
+++ b/dom/serviceworkers/ServiceWorkerInfo.cpp
@@ -113,17 +113,17 @@ ServiceWorkerInfo::DetachDebugger()
   return mServiceWorkerPrivate->DetachDebugger();
 }
 
 namespace {
 
 class ChangeStateUpdater final : public Runnable
 {
 public:
-  ChangeStateUpdater(const nsTArray<ServiceWorker*>& aInstances,
+  ChangeStateUpdater(const nsTArray<ServiceWorkerInfo::Listener*>& aInstances,
                      ServiceWorkerState aState)
     : Runnable("dom::ChangeStateUpdater")
     , mState(aState)
   {
     for (size_t i = 0; i < aInstances.Length(); ++i) {
       mInstances.AppendElement(aInstances[i]);
     }
   }
@@ -132,17 +132,17 @@ public:
   {
     for (size_t i = 0; i < mInstances.Length(); ++i) {
       mInstances[i]->SetState(mState);
     }
     return NS_OK;
   }
 
 private:
-  AutoTArray<RefPtr<ServiceWorker>, 1> mInstances;
+  AutoTArray<RefPtr<ServiceWorkerInfo::Listener>, 1> mInstances;
   ServiceWorkerState mState;
 };
 
 }
 
 void
 ServiceWorkerInfo::UpdateState(ServiceWorkerState aState)
 {
@@ -220,43 +220,30 @@ static uint64_t gServiceWorkerInfoCurren
 
 uint64_t
 ServiceWorkerInfo::GetNextID() const
 {
   return ++gServiceWorkerInfoCurrentID;
 }
 
 void
-ServiceWorkerInfo::AddServiceWorker(ServiceWorker* aWorker)
+ServiceWorkerInfo::AddListener(Listener* aListener)
 {
-  MOZ_DIAGNOSTIC_ASSERT(aWorker);
-#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
-  nsAutoString workerURL;
-  aWorker->GetScriptURL(workerURL);
-  MOZ_DIAGNOSTIC_ASSERT(
-    workerURL.Equals(NS_ConvertUTF8toUTF16(mDescriptor.ScriptURL())));
-#endif
-  MOZ_ASSERT(!mInstances.Contains(aWorker));
+  MOZ_DIAGNOSTIC_ASSERT(aListener);
+  MOZ_ASSERT(!mInstances.Contains(aListener));
 
-  mInstances.AppendElement(aWorker);
-  aWorker->SetState(State());
+  mInstances.AppendElement(aListener);
+  aListener->SetState(State());
 }
 
 void
-ServiceWorkerInfo::RemoveServiceWorker(ServiceWorker* aWorker)
+ServiceWorkerInfo::RemoveListener(Listener* aListener)
 {
-  MOZ_DIAGNOSTIC_ASSERT(aWorker);
-#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
-  nsAutoString workerURL;
-  aWorker->GetScriptURL(workerURL);
-  MOZ_DIAGNOSTIC_ASSERT(
-    workerURL.Equals(NS_ConvertUTF8toUTF16(mDescriptor.ScriptURL())));
-#endif
-
-  DebugOnly<bool> removed = mInstances.RemoveElement(aWorker);
+  MOZ_DIAGNOSTIC_ASSERT(aListener);
+  DebugOnly<bool> removed = mInstances.RemoveElement(aListener);
   MOZ_ASSERT(removed);
 }
 
 void
 ServiceWorkerInfo::PostMessage(ipc::StructuredCloneData&& aData,
                                const ClientInfo& aClientInfo,
                                const ClientState& aClientState)
 {

--- a/dom/serviceworkers/ServiceWorkerInfo.h
+++ b/dom/serviceworkers/ServiceWorkerInfo.h
@@ -7,33 +7,41 @@
 #ifndef mozilla_dom_serviceworkerinfo_h
 #define mozilla_dom_serviceworkerinfo_h
 
 #include "MainThreadUtils.h"
 #include "mozilla/dom/ServiceWorkerBinding.h" // For ServiceWorkerState
 #include "mozilla/dom/WorkerCommon.h"
 #include "mozilla/OriginAttributes.h"
 #include "nsIServiceWorkerManager.h"
-#include "ServiceWorker.h"
 
 namespace mozilla {
 namespace dom {
 
 class ClientInfoAndState;
 class ServiceWorkerPrivate;
 
 /*
  * Wherever the spec treats a worker instance and a description of said worker
  * as the same thing; i.e. "Resolve foo with
  * _GetNewestWorker(serviceWorkerRegistration)", we represent the description
  * by this class and spawn a ServiceWorker in the right global when required.
  */
 class ServiceWorkerInfo final : public nsIServiceWorkerInfo
-                              , public ServiceWorker::Inner
 {
+public:
+  class Listener
+  {
+  public:
+    virtual void
+    SetState(ServiceWorkerState aState) = 0;
+
+    NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+  };
+
 private:
   nsCOMPtr<nsIPrincipal> mPrincipal;
   ServiceWorkerDescriptor mDescriptor;
   const nsString mCacheName;
   OriginAttributes mOriginAttributes;
 
   // This LoadFlags is only applied to imported scripts, since the main script
   // has already been downloaded when performing the bytecheck. This LoadFlag is
@@ -55,17 +63,17 @@ private:
   PRTime mActivatedTime;
   PRTime mRedundantTime;
 
   // We hold rawptrs since the ServiceWorker constructor and destructor ensure
   // addition and removal.
   //
   // There is a high chance of there being at least one ServiceWorker
   // associated with this all the time.
-  AutoTArray<ServiceWorker*, 1> mInstances;
+  AutoTArray<Listener*, 1> mInstances;
 
   RefPtr<ServiceWorkerPrivate> mServiceWorkerPrivate;
   bool mSkipWaitingFlag;
 
   enum {
     Unknown,
     Enabled,
     Disabled
@@ -73,32 +81,31 @@ private:
 
   ~ServiceWorkerInfo();
 
   // Generates a unique id for the service worker, with zero being treated as
   // invalid.
   uint64_t
   GetNextID() const;
 
-  // ServiceWorker::Inner implementation
-  virtual void
-  AddServiceWorker(ServiceWorker* aWorker) override;
-
-  virtual void
-  RemoveServiceWorker(ServiceWorker* aWorker) override;
-
-  virtual void
-  PostMessage(ipc::StructuredCloneData&& aData,
-              const ClientInfo& aClientInfo,
-              const ClientState& aClientState) override;
-
 public:
   NS_DECL_ISUPPORTS
   NS_DECL_NSISERVICEWORKERINFO
 
+  void
+  AddListener(Listener* aListener);
+
+  void
+  RemoveListener(Listener* aListener);
+
+  void
+  PostMessage(ipc::StructuredCloneData&& aData,
+              const ClientInfo& aClientInfo,
+              const ClientState& aClientState);
+
   class ServiceWorkerPrivate*
   WorkerPrivate() const
   {
     MOZ_ASSERT(mServiceWorkerPrivate);
     return mServiceWorkerPrivate;
   }
 
   nsIPrincipal*

--- a/dom/serviceworkers/ServiceWorkerRegistrar.cpp
+++ b/dom/serviceworkers/ServiceWorkerRegistrar.cpp
@@ -10,16 +10,17 @@
 #include "mozilla/net/MozURL.h"
 
 #include "nsIEventTarget.h"
 #include "nsIInputStream.h"
 #include "nsILineInputStream.h"
 #include "nsIObserverService.h"
 #include "nsIOutputStream.h"
 #include "nsISafeOutputStream.h"
+#include "nsIServiceWorkerManager.h"
 
 #include "MainThreadUtils.h"
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/CycleCollectedJSContext.h"
 #include "mozilla/dom/StorageActivityService.h"
 #include "mozilla/ErrorNames.h"
 #include "mozilla/ipc/BackgroundChild.h"
 #include "mozilla/ipc/BackgroundParent.h"
@@ -31,16 +32,17 @@
 #include "nsAppDirectoryServiceDefs.h"
 #include "nsContentUtils.h"
 #include "nsDirectoryServiceUtils.h"
 #include "nsNetCID.h"
 #include "nsNetUtil.h"
 #include "nsServiceManagerUtils.h"
 #include "nsThreadUtils.h"
 #include "nsXULAppAPI.h"
+#include "ServiceWorkerUtils.h"
 
 using namespace mozilla::ipc;
 
 namespace mozilla {
 namespace dom {
 
 namespace {
 

--- a/dom/serviceworkers/moz.build
+++ b/dom/serviceworkers/moz.build
@@ -27,16 +27,17 @@ EXPORTS.mozilla.dom += [
 ]
 
 UNIFIED_SOURCES += [
     'ServiceWorker.cpp',
     'ServiceWorkerContainer.cpp',
     'ServiceWorkerContainerImpl.cpp',
     'ServiceWorkerDescriptor.cpp',
     'ServiceWorkerEvents.cpp',
+    'ServiceWorkerImpl.cpp',
     'ServiceWorkerInfo.cpp',
     'ServiceWorkerInterceptController.cpp',
     'ServiceWorkerJob.cpp',
     'ServiceWorkerJobQueue.cpp',
     'ServiceWorkerManager.cpp',
     'ServiceWorkerManagerChild.cpp',
     'ServiceWorkerManagerParent.cpp',
     'ServiceWorkerManagerService.cpp',

--- a/dom/tests/mochitest/general/test_consoleAPI.html
+++ b/dom/tests/mochitest/general/test_consoleAPI.html
@@ -27,16 +27,17 @@ function doTest() {
     "exception": "function",
     "debug": "function",
     "trace": "function",
     "dir": "function",
     "group": "function",
     "groupCollapsed": "function",
     "groupEnd": "function",
     "time": "function",
+    "timeLog": "function",
     "timeEnd": "function",
     "profile": "function",
     "profileEnd": "function",
     "assert": "function",
     "count": "function",
     "table": "function",
     "clear": "function",
     "dirxml": "function",

--- a/dom/tests/mochitest/general/test_interfaces.js
+++ b/dom/tests/mochitest/general/test_interfaces.js
@@ -252,38 +252,32 @@ var interfaceNamesInGlobalScope =
     {name: "CSSMediaRule", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSMozDocumentRule", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSNamespaceRule", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSPageRule", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
-    {name: "CSSPrimitiveValue", insecureContext: true},
-// IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSPseudoElement", insecureContext: true, release: false},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSRule", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSRuleList", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSStyleDeclaration", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSStyleRule", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSStyleSheet", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSSupportsRule", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CSSTransition", insecureContext: true, release: false},
 // IMPORTANT: Do not change this list without review from a DOM peer!
-    {name: "CSSValue", insecureContext: true},
-// IMPORTANT: Do not change this list without review from a DOM peer!
-    {name: "CSSValueList", insecureContext: true},
-// IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CustomElementRegistry", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "CustomEvent", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "DataTransfer", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "DataTransferItem", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
@@ -810,24 +804,20 @@ var interfaceNamesInGlobalScope =
     {name: "PushSubscription", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "PushSubscriptionOptions", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "RadioNodeList", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "Range", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
-    {name: "Rect", insecureContext: true},
-// IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "Request", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "Response", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
-    {name: "RGBColor", insecureContext: true},
-// IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "RTCCertificate", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "RTCDataChannel", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "RTCDataChannelEvent", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!
     {name: "RTCDTMFSender", insecureContext: true},
 // IMPORTANT: Do not change this list without review from a DOM peer!

deleted file mode 100644
--- a/dom/webidl/CSSPrimitiveValue.webidl
+++ /dev/null
@@ -1,54 +0,0 @@
-/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* 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/.
- */
-
-interface CSSPrimitiveValue : CSSValue {
-
-  // UnitTypes
-  const unsigned short      CSS_UNKNOWN                    = 0;
-  const unsigned short      CSS_NUMBER                     = 1;
-  const unsigned short      CSS_PERCENTAGE                 = 2;
-  const unsigned short      CSS_EMS                        = 3;
-  const unsigned short      CSS_EXS                        = 4;
-  const unsigned short      CSS_PX                         = 5;
-  const unsigned short      CSS_CM                         = 6;
-  const unsigned short      CSS_MM                         = 7;
-  const unsigned short      CSS_IN                         = 8;
-  const unsigned short      CSS_PT                         = 9;
-  const unsigned short      CSS_PC                         = 10;
-  const unsigned short      CSS_DEG                        = 11;
-  const unsigned short      CSS_RAD                        = 12;
-  const unsigned short      CSS_GRAD                       = 13;
-  const unsigned short      CSS_MS                         = 14;
-  const unsigned short      CSS_S                          = 15;
-  const unsigned short      CSS_HZ                         = 16;
-  const unsigned short      CSS_KHZ                        = 17;
-  const unsigned short      CSS_DIMENSION                  = 18;
-  const unsigned short      CSS_STRING                     = 19;
-  const unsigned short      CSS_URI                        = 20;
-  const unsigned short      CSS_IDENT                      = 21;
-  const unsigned short      CSS_ATTR                       = 22;
-  const unsigned short      CSS_COUNTER                    = 23;
-  const unsigned short      CSS_RECT                       = 24;
-  const unsigned short      CSS_RGBCOLOR                   = 25;
-
-  readonly attribute unsigned short   primitiveType;
-  [Throws]
-  void               setFloatValue(unsigned short unitType,
-                                   float floatValue);
-  [Throws]
-  float              getFloatValue(unsigned short unitType);
-  [Throws]
-  void               setStringValue(unsigned short stringType,
-                                    DOMString stringValue);
-  [Throws]
-  DOMString          getStringValue();
-  [Throws]
-  void               getCounterValue();  // always throws
-  [Throws]
-  Rect               getRectValue();
-  [Throws]
-  RGBColor           getRGBColorValue();
-};

deleted file mode 100644
--- a/dom/webidl/CSSValue.webidl
+++ /dev/null
@@ -1,19 +0,0 @@
-/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* 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/.
- */
-
-interface CSSValue {
-
-  // UnitTypes
-  const unsigned short      CSS_INHERIT                    = 0;
-  const unsigned short      CSS_PRIMITIVE_VALUE            = 1;
-  const unsigned short      CSS_VALUE_LIST                 = 2;
-  const unsigned short      CSS_CUSTOM                     = 3;
-
-           [Throws]
-           attribute DOMString        cssText;
-
-  readonly attribute unsigned short   cssValueType;
-};

deleted file mode 100644
--- a/dom/webidl/CSSValueList.webidl
+++ /dev/null
@@ -1,10 +0,0 @@
-/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* 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/.
- */
-
-interface CSSValueList : CSSValue {
-         readonly attribute unsigned long    length;
-  getter CSSValue?          item(unsigned long index);
-};

--- a/dom/webidl/Console.webidl
+++ b/dom/webidl/Console.webidl
@@ -49,16 +49,18 @@ namespace console {
   void groupCollapsed(any... data);
   [UseCounter]
   void groupEnd();
 
   // Timing
   [UseCounter]
   void time(optional DOMString label = "default");
   [UseCounter]
+  void timeLog(optional DOMString label = "default", any... data);
+  [UseCounter]
   void timeEnd(optional DOMString label = "default");
 
   // Mozilla only or Webcompat methods
 
   [UseCounter]
   void _exception(any... data);
   [UseCounter]
   void timeStamp(optional any data);
@@ -116,17 +118,17 @@ dictionary ConsoleStackEntry {
   DOMString functionName = "";
   DOMString? asyncCause;
 };
 
 dictionary ConsoleTimerStart {
   DOMString name = "";
 };
 
-dictionary ConsoleTimerEnd {
+dictionary ConsoleTimerLogOrEnd {
   DOMString name = "";
   double duration = 0;
 };
 
 dictionary ConsoleTimerError {
   DOMString error = "";
   DOMString name = "";
 };
@@ -160,32 +162,34 @@ interface ConsoleInstance {
 
   // Grouping
   void group(any... data);
   void groupCollapsed(any... data);
   void groupEnd();
 
   // Timing
   void time(optional DOMString label = "default");
+  void timeLog(optional DOMString label = "default", any... data);
   void timeEnd(optional DOMString label = "default");
 
   // Mozilla only or Webcompat methods
 
   void _exception(any... data);
   void timeStamp(optional any data);
 
   void profile(any... data);
   void profileEnd(any... data);
 };
 
 callback ConsoleInstanceDumpCallback = void (DOMString message);
 
 enum ConsoleLogLevel {
-  "All", "Debug", "Log", "Info", "Clear", "Trace", "TimeEnd", "Time", "Group",
-  "GroupEnd", "Profile", "ProfileEnd", "Dir", "Dirxml", "Warn", "Error", "Off"
+  "All", "Debug", "Log", "Info", "Clear", "Trace", "TimeLog", "TimeEnd", "Time",
+  "Group", "GroupEnd", "Profile", "ProfileEnd", "Dir", "Dirxml", "Warn", "Error",
+  "Off"
 };
 
 dictionary ConsoleInstanceOptions {
   // An optional function to intercept all strings written to stdout.
   ConsoleInstanceDumpCallback dump;
 
   // An optional prefix string to be printed before the actual logged message.
   DOMString prefix = "";

deleted file mode 100644
--- a/dom/webidl/RGBColor.webidl
+++ /dev/null
@@ -1,17 +0,0 @@
-/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* 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/.
- *
- * The origin of this IDL file is
- * http://www.w3.org/TR/DOM-Level-2-Style/css.html#CSS-RGBColor
- */
-
-interface RGBColor {
-  readonly attribute CSSPrimitiveValue  red;
-  readonly attribute CSSPrimitiveValue  green;
-  readonly attribute CSSPrimitiveValue  blue;
-
-  // mozilla specific
-  readonly attribute CSSPrimitiveValue alpha;
-};

deleted file mode 100644
--- a/dom/webidl/Rect.webidl
+++ /dev/null
@@ -1,12 +0,0 @@
-/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* 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/.
- */
-
-interface Rect {
-  readonly attribute CSSPrimitiveValue top;
-  readonly attribute CSSPrimitiveValue right;
-  readonly attribute CSSPrimitiveValue bottom;
-  readonly attribute CSSPrimitiveValue left;
-};

--- a/dom/webidl/moz.build
+++ b/dom/webidl/moz.build
@@ -436,27 +436,24 @@ WEBIDL_FILES = [
     'CSSImportRule.webidl',
     'CSSKeyframeRule.webidl',
     'CSSKeyframesRule.webidl',
     'CSSLexer.webidl',
     'CSSMediaRule.webidl',
     'CSSMozDocumentRule.webidl',
     'CSSNamespaceRule.webidl',
     'CSSPageRule.webidl',
-    'CSSPrimitiveValue.webidl',
     'CSSPseudoElement.webidl',
     'CSSRule.webidl',
     'CSSRuleList.webidl',
     'CSSStyleDeclaration.webidl',
     'CSSStyleRule.webidl',
     'CSSStyleSheet.webidl',
     'CSSSupportsRule.webidl',
     'CSSTransition.webidl',
-    'CSSValue.webidl',
-    'CSSValueList.webidl',
     'CustomElementRegistry.webidl',
     'DataTransfer.webidl',
     'DataTransferItem.webidl',
     'DataTransferItemList.webidl',
     'DecoderDoctorNotification.webidl',
     'DedicatedWorkerGlobalScope.webidl',
     'DelayNode.webidl',
     'DeviceMotionEvent.webidl',
@@ -733,20 +730,18 @@ WEBIDL_FILES = [
     'PushEvent.webidl',
     'PushManager.webidl',
     'PushManager.webidl',
     'PushMessageData.webidl',
     'PushSubscription.webidl',
     'PushSubscriptionOptions.webidl',
     'RadioNodeList.webidl',
     'Range.webidl',
-    'Rect.webidl',
     'Request.webidl',
     'Response.webidl',
-    'RGBColor.webidl',
     'RTCStatsReport.webidl',
     'Screen.webidl',
     'ScreenOrientation.webidl',
     'ScriptProcessorNode.webidl',
     'ScrollAreaEvent.webidl',
     'ScrollBoxObject.webidl',
     'Selection.webidl',
     'ServiceWorker.webidl',

--- a/editor/libeditor/HTMLAbsPositionEditor.cpp
+++ b/editor/libeditor/HTMLAbsPositionEditor.cpp
@@ -9,17 +9,16 @@
 #include "HTMLEditorObjectResizerUtils.h"
 #include "HTMLEditRules.h"
 #include "HTMLEditUtils.h"
 #include "TextEditUtils.h"
 #include "mozilla/EditAction.h"
 #include "mozilla/EditorUtils.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/TextEditRules.h"
-#include "mozilla/dom/CSSPrimitiveValueBinding.h"
 #include "mozilla/dom/Selection.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/dom/EventTarget.h"
 #include "mozilla/mozalloc.h"
 #include "nsAString.h"
 #include "nsAlgorithm.h"
 #include "nsCOMPtr.h"
 #include "nsComputedDOMStyle.h"

--- a/editor/libeditor/HTMLAnonymousNodeEditor.cpp
+++ b/editor/libeditor/HTMLAnonymousNodeEditor.cpp
@@ -1,16 +1,15 @@
 /* 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/. */
 
 #include "mozilla/HTMLEditor.h"
 
 #include "mozilla/Attributes.h"
-#include "mozilla/dom/CSSPrimitiveValueBinding.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/dom/EventTarget.h"
 #include "mozilla/mozalloc.h"
 #include "nsAString.h"
 #include "nsCOMPtr.h"
 #include "nsComputedDOMStyle.h"
 #include "nsDebug.h"
 #include "nsError.h"

--- a/gfx/thebes/gfxFont.cpp
+++ b/gfx/thebes/gfxFont.cpp
@@ -4206,25 +4206,26 @@ gfxFontStyle::gfxFontStyle(FontSlantStyl
         NS_WARNING("null language");
         language = nsGkAtoms::x_western;
     }
 }
 
 PLDHashNumber
 gfxFontStyle::Hash() const
 {
-    return mozilla::HashGeneric(systemFont, style.ForHash(),
-                                stretch.ForHash(), weight.ForHash(),
-                                size, sizeAdjust,
-                                nsRefPtrHashKey<nsAtom>::HashKey(language));
-    /* XXX
-    return (style + (systemFont << 7) + (weight.ForHash() << 8) +
-            uint32_t(size*1000) + int32_t(sizeAdjust*1000)) ^
-            nsRefPtrHashKey<nsAtom>::HashKey(language);
-    */
+    uint32_t hash =
+        variationSettings.IsEmpty()
+            ? 0
+            : mozilla::HashBytes(variationSettings.Elements(),
+                                 variationSettings.Length() *
+                                     sizeof(gfxFontVariation));
+    return mozilla::AddToHash(hash, systemFont, style.ForHash(),
+                              stretch.ForHash(), weight.ForHash(),
+                              size, int32_t(sizeAdjust * 1000.0f),
+                              nsRefPtrHashKey<nsAtom>::HashKey(language));
 }
 
 void
 gfxFontStyle::AdjustForSubSuperscript(int32_t aAppUnitsPerDevPixel)
 {
     MOZ_ASSERT(variantSubSuper != NS_FONT_VARIANT_POSITION_NORMAL &&
                baselineOffset == 0,
                "can't adjust this style for sub/superscript");

--- a/gfx/thebes/gfxFontEntry.cpp
+++ b/gfx/thebes/gfxFontEntry.cpp
@@ -1519,18 +1519,16 @@ WeightDistance(const gfxFontEntry* aFont
         if (distance < 0.0) {
             distance = kReverseDistance - distance;
         }
         distance += addedDistance;
     }
     return distance;
 }
 
-#define MAX_DISTANCE 1.0e20 // >> than any WeightStyleStretchDistance result
-
 static inline double
 WeightStyleStretchDistance(gfxFontEntry* aFontEntry,
                            const gfxFontStyle& aTargetStyle)
 {
     double stretchDist = StretchDistance(aFontEntry, aTargetStyle.stretch);
     double styleDist = StyleDistance(aFontEntry, aTargetStyle.style);
     double weightDist = WeightDistance(aFontEntry, aTargetStyle.weight);
 
@@ -1620,17 +1618,17 @@ gfxFontFamily::FindAllFontsForStyle(cons
     // given but the 99% use case is only a single font entry per
     // weight/style/stretch distance value. To optimize this, only add entries
     // to the matched font array when another entry already has the same
     // weight/style/stretch distance and add the last matched font entry. For
     // normal platform fonts with a single font entry for each
     // weight/style/stretch combination, only the last matched font entry will
     // be added.
 
-    double minDistance = MAX_DISTANCE;
+    double minDistance = INFINITY;
     gfxFontEntry* matched = nullptr;
     // iterate in forward order so that faces like 'Bold' are matched before
     // matching style distance faces such as 'Bold Outline' (see bug 1185812)
     for (uint32_t i = 0; i < count; i++) {
         fe = mAvailableFonts[i];
         // weight/style/stretch priority: stretch >> style >> weight
         double distance = WeightStyleStretchDistance(fe, aFontStyle);
         if (distance < minDistance) {
@@ -1730,137 +1728,91 @@ gfxFontFamily::ContainsFace(gfxFontEntry
 #endif
 
 void gfxFontFamily::LocalizedName(nsAString& aLocalizedName)
 {
     // just return the primary name; subclasses should override
     aLocalizedName = mName;
 }
 
-// metric for how close a given font matches a style
-static float
-CalcStyleMatch(gfxFontEntry *aFontEntry, const gfxFontStyle *aStyle)
-{
-    float rank = 0;
-    if (aStyle) {
-        // TODO: stretch
-
-        // italics
-        bool wantUpright = aStyle->style.IsNormal();
-        if (aFontEntry->IsUpright() == wantUpright) {
-            rank += 5000.0f;
-        }
-
-        // measure of closeness of weight to the desired value
-        if (aFontEntry->Weight().Min() > aStyle->weight) {
-            rank += 1000.0f - (aFontEntry->Weight().Min() - aStyle->weight);
-        } else if (aFontEntry->Weight().Max() < aStyle->weight) {
-            rank += 1000.0f - (aStyle->weight - aFontEntry->Weight().Max());
-        } else {
-            rank += 2000.0f; // the font supports the exact weight wanted
-        }
-    } else {
-        // if no font to match, prefer non-bold, non-italic fonts
-        if (aFontEntry->IsUpright()) {
-            rank += 2000.0f;
-        }
-        if (aFontEntry->Weight().Min() <= FontWeight(500)) {
-            rank += 1000.0f;
-        }
-    }
-
-    return rank;
-}
-
-#define RANK_MATCHED_CMAP   10000.0f
-
 void
-gfxFontFamily::FindFontForChar(GlobalFontMatch *aMatchData)
+gfxFontFamily::FindFontForChar(GlobalFontMatch* aMatchData)
 {
     if (mFamilyCharacterMapInitialized && !TestCharacterMap(aMatchData->mCh)) {
         // none of the faces in the family support the required char,
         // so bail out immediately
         return;
     }
 
-    gfxFontEntry *fe =
-        FindFontForStyle(aMatchData->mStyle ? *aMatchData->mStyle
-                                            : gfxFontStyle(),
-                         true);
+    gfxFontEntry* fe =
+        FindFontForStyle(aMatchData->mStyle, /*aIgnoreSizeTolerance*/ true);
+    if (!fe || fe->SkipDuringSystemFallback()) {
+        return;
+    }
 
-    if (fe && !fe->SkipDuringSystemFallback()) {
-        float rank = 0;
+    float distance = INFINITY;
 
-        if (fe->HasCharacter(aMatchData->mCh)) {
-            rank += RANK_MATCHED_CMAP;
-            aMatchData->mCount++;
-
-            LogModule* log = gfxPlatform::GetLog(eGfxLog_textrun);
+    if (fe->HasCharacter(aMatchData->mCh)) {
+        aMatchData->mCount++;
 
-            if (MOZ_UNLIKELY(MOZ_LOG_TEST(log, LogLevel::Debug))) {
-                uint32_t unicodeRange = FindCharUnicodeRange(aMatchData->mCh);
-                Script script = GetScriptCode(aMatchData->mCh);
-                MOZ_LOG(log, LogLevel::Debug,\
-                       ("(textrun-systemfallback-fonts) char: u+%6.6x "
-                        "unicode-range: %d script: %d match: [%s]\n",
-                        aMatchData->mCh,
-                        unicodeRange, int(script),
-                        NS_ConvertUTF16toUTF8(fe->Name()).get()));
-            }
+        LogModule* log = gfxPlatform::GetLog(eGfxLog_textrun);
 
-            // omitting from original windows code -- family name, lang group, pitch
-            // not available in current FontEntry implementation
-            rank += CalcStyleMatch(fe, aMatchData->mStyle);
-        } else if (!fe->IsNormalStyle()) {
-            // If style/weight/stretch was not Normal, see if we can
-            // fall back to a next-best face (e.g. Arial Black -> Bold,
-            // or Arial Narrow -> Regular).
-            GlobalFontMatch data(aMatchData->mCh, aMatchData->mStyle);
-            SearchAllFontsForChar(&data);
-            if (data.mMatchRank >= RANK_MATCHED_CMAP) {
-                fe = data.mBestMatch;
-                rank = data.mMatchRank;
-            } else {
-                return;
-            }
-        } else {
-            return;
+        if (MOZ_UNLIKELY(MOZ_LOG_TEST(log, LogLevel::Debug))) {
+            uint32_t unicodeRange = FindCharUnicodeRange(aMatchData->mCh);
+            Script script = GetScriptCode(aMatchData->mCh);
+            MOZ_LOG(log, LogLevel::Debug,\
+                   ("(textrun-systemfallback-fonts) char: u+%6.6x "
+                    "unicode-range: %d script: %d match: [%s]\n",
+                    aMatchData->mCh,
+                    unicodeRange, int(script),
+                    NS_ConvertUTF16toUTF8(fe->Name()).get()));
         }
 
-        aMatchData->mCmapsTested++;
-
-        // xxx - add whether AAT font with morphing info for specific lang groups
+        distance = WeightStyleStretchDistance(fe, aMatchData->mStyle);
+    } else if (!fe->IsNormalStyle()) {
+        // If style/weight/stretch was not Normal, see if we can
+        // fall back to a next-best face (e.g. Arial Black -> Bold,
+        // or Arial Narrow -> Regular).
+        GlobalFontMatch data(aMatchData->mCh, aMatchData->mStyle);
+        SearchAllFontsForChar(&data);
+        if (std::isfinite(data.mMatchDistance)) {
+            fe = data.mBestMatch;
+            distance = data.mMatchDistance;
+        }
+    }
+    aMatchData->mCmapsTested++;
 
-        if (rank > aMatchData->mMatchRank
-            || (rank == aMatchData->mMatchRank &&
-                Compare(fe->Name(), aMatchData->mBestMatch->Name()) > 0))
-        {
-            aMatchData->mBestMatch = fe;
-            aMatchData->mMatchedFamily = this;
-            aMatchData->mMatchRank = rank;
-        }
+    if (std::isinf(distance)) {
+        return;
+    }
+
+    if (distance < aMatchData->mMatchDistance ||
+        (distance == aMatchData->mMatchDistance &&
+         Compare(fe->Name(), aMatchData->mBestMatch->Name()) > 0)) {
+        aMatchData->mBestMatch = fe;
+        aMatchData->mMatchedFamily = this;
+        aMatchData->mMatchDistance = distance;
     }
 }
 
 void
-gfxFontFamily::SearchAllFontsForChar(GlobalFontMatch *aMatchData)
+gfxFontFamily::SearchAllFontsForChar(GlobalFontMatch* aMatchData)
 {
     uint32_t i, numFonts = mAvailableFonts.Length();
     for (i = 0; i < numFonts; i++) {
         gfxFontEntry *fe = mAvailableFonts[i];
         if (fe && fe->HasCharacter(aMatchData->mCh)) {
-            float rank = RANK_MATCHED_CMAP;
-            rank += CalcStyleMatch(fe, aMatchData->mStyle);
-            if (rank > aMatchData->mMatchRank
-                || (rank == aMatchData->mMatchRank &&
+            float distance = WeightStyleStretchDistance(fe, aMatchData->mStyle);
+            if (distance < aMatchData->mMatchDistance
+                || (distance == aMatchData->mMatchDistance &&
                     Compare(fe->Name(), aMatchData->mBestMatch->Name()) > 0))
             {
                 aMatchData->mBestMatch = fe;
                 aMatchData->mMatchedFamily = this;
-                aMatchData->mMatchRank = rank;
+                aMatchData->mMatchDistance = distance;
             }
         }
     }
 }
 
 /*virtual*/
 gfxFontFamily::~gfxFontFamily()
 {

--- a/gfx/thebes/gfxFontEntry.h
+++ b/gfx/thebes/gfxFontEntry.h
@@ -19,16 +19,17 @@
 #include "MainThreadUtils.h"
 #include "nsUnicodeScriptCodes.h"
 #include "nsDataHashtable.h"
 #include "harfbuzz/hb.h"
 #include "mozilla/FontPropertyTypes.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/UniquePtr.h"
 #include "mozilla/WeakPtr.h"
+#include <math.h>
 
 typedef struct gr_face gr_face;
 
 #ifdef DEBUG
 #include <stdio.h>
 #endif
 
 struct gfxFontStyle;
@@ -685,30 +686,29 @@ gfxFontEntry::SupportsBold()
            ((mRangeFlags & RangeFlags::eAutoWeight) ==
                RangeFlags::eAutoWeight &&
             HasBoldVariableWeight());
 }
 
 // used when iterating over all fonts looking for a match for a given character
 struct GlobalFontMatch {
     GlobalFontMatch(const uint32_t aCharacter,
-                    const gfxFontStyle *aStyle) :
-        mCh(aCharacter), mStyle(aStyle),
-        mMatchRank(0.0f), mCount(0), mCmapsTested(0)
+                    const gfxFontStyle& aStyle) :
+        mStyle(aStyle), mCh(aCharacter),
+        mCount(0), mCmapsTested(0), mMatchDistance(INFINITY)
         {
-
         }
 
+    RefPtr<gfxFontEntry>   mBestMatch;   // current best match
+    RefPtr<gfxFontFamily>  mMatchedFamily; // the family it belongs to
+    const gfxFontStyle&    mStyle;       // style to match
     const uint32_t         mCh;          // codepoint to be matched
-    const gfxFontStyle*    mStyle;       // style to match
-    float                  mMatchRank;   // metric indicating closest match
-    RefPtr<gfxFontEntry> mBestMatch;   // current best match
-    RefPtr<gfxFontFamily> mMatchedFamily; // the family it belongs to
     uint32_t               mCount;       // number of fonts matched
     uint32_t               mCmapsTested; // number of cmaps tested
+    float                  mMatchDistance; // metric indicating closest match
 };
 
 class gfxFontFamily {
 public:
     // Used by stylo
     NS_INLINE_DECL_THREADSAFE_REFCOUNTING(gfxFontFamily)
 
     explicit gfxFontFamily(const nsAString& aName) :
@@ -781,20 +781,20 @@ public:
 
     virtual void
     FindAllFontsForStyle(const gfxFontStyle& aFontStyle,
                          nsTArray<gfxFontEntry*>& aFontEntryList,
                          bool aIgnoreSizeTolerance = false);
 
     // checks for a matching font within the family
     // used as part of the font fallback process
-    void FindFontForChar(GlobalFontMatch *aMatchData);
+    void FindFontForChar(GlobalFontMatch* aMatchData);
 
     // checks all fonts for a matching font within the family
-    void SearchAllFontsForChar(GlobalFontMatch *aMatchData);
+    void SearchAllFontsForChar(GlobalFontMatch* aMatchData);
 
     // read in other family names, if any, and use functor to add each into cache
     virtual void ReadOtherFamilyNames(gfxPlatformFontList *aPlatformFontList);
 
     // helper method for reading localized family names from the name table
     // of a single face
     static void ReadOtherFamilyNamesForFace(const nsAString& aFamilyName,
                                             const char *aNameData,