Bug 1559207 - Make XULPersist::AttributeChanged a bit faster in the common case, r=bdahl GetAttr returns false if the attribute isn't there at all. Differential Revision: https://phabricator.services.mozilla.com/D34920

Bug 1557730 - Enable HTTPResponseProcessSelection for windowProxy_transplant test, r=mccr8 Differential Revision: https://phabricator.services.mozilla.com/D34907

Bug 1558923 - Remove nsContentUtils::GetThreadSafe{ASCII,UTF8}Origin, r=valentin Differential Revision: https://phabricator.services.mozilla.com/D34767

Bug 1558923 - Simplify URL API, r=valentin Differential Revision: https://phabricator.services.mozilla.com/D34766

Backed out 2 changesets (bug 1550137) for bc failures at browser_masterPassword.js. CLOSED TREE Backed out changeset d7b5c95addb1 (bug 1550137) Backed out changeset db2092bd295b (bug 1550137)

Backed out changeset 3876241cc1ec (bug 1558506) for mochitest failrues at test_contextmenu_list.xul. CLOSED TREE

Backed out changeset 62ac95a65617 (bug 1495621) for marionette mozprocess timed out failures.

Backed out 5 changesets (bug 1510569) for bustages on BrowserChild.cpp . CLOSED TREE Backed out changeset 4f0f5351be8b (bug 1510569) Backed out changeset 14bbe0916bdd (bug 1510569) Backed out changeset 19e734aeffa9 (bug 1510569) Backed out changeset abb51690fd32 (bug 1510569) Backed out changeset 1bf1907ee0c9 (bug 1510569)

Bug 1557548 - part2 : enable wpt 'navigate_cue_position.html'. r=heycam Disable on Windows is because sometime iframe can't load successfully, which makes our test file showing wrong image. Differential Revision: https://phabricator.services.mozilla.com/D34778

Bug 1557548 - part1 : remove 'controls' attribute from video. r=heycam It's no need to add 'controls' attribute in this test because it's totally unrelated with navigation and we even have to add extra offset for the cue text in the reference file. Differential Revision: https://phabricator.services.mozilla.com/D34777

Bug 1555836 - use the pref to dynamically switch vtt debug log. r=heycam It would be more convenient to use the pref to dynamically switch vtt debug log on/off without changing any code. Differential Revision: https://phabricator.services.mozilla.com/D33220

Bug 1510569 - Port Content:LoadURIResult message to IPDL r=mconley The `WebProgress#sendLoadCallResult` method only existed to send a empty async message and was only called from the `WebNavigationChild`. Since `WebNavigationChild` is in the process of being removed, it makes sense to inline the replaced method into its call site. Differential Revision: https://phabricator.services.mozilla.com/D34566

Bug 1510569 - Move Content:BrowserChildReady from WebProgressChild.jsm into the browser child frame script r=mconley Differential Revision: https://phabricator.services.mozilla.com/D34565

Bug 1510569 - Order the RefreshBlocker's messages to the parent after the BrowserChild's r=Ehsan Differential Revision: https://phabricator.services.mozilla.com/D34564

Bug 1510569 - Port onLocationChange notifications inside WebProgressChild.jsm to C++ r=Ehsan Differential Revision: https://phabricator.services.mozilla.com/D34563

Bug 1510569 - Correctly reconstruct nsIRequest in tab parent r=Ehsan When `TabParent::ReconstructWebProgressRequest` was introduced in 31b206e2046f63af31424489e3d61d7761805878, it mistakenly was unconditionally constructing an `nsIRequest` from the received `RequestData`, even when the URI was null. Additionally `ReconstructWebProgressRequest` has been updated to use the Gecko style for out parameters (accepting an `nsIFoo**` and passing `getter_AddRefs(...)` instead of `nsCOMPtr<nsIFoo>&`). Differential Revision: https://phabricator.services.mozilla.com/D34445

Bug 1558540 - Show report checkbox in uninstall addon dialog only for supported addon types. r=jaws,mstriemer Differential Revision: https://phabricator.services.mozilla.com/D34643

Bug 1536871 - Make 'line-height: normal' return the 'normal' keyword from getComputedStyle() on Nightly and Early Beta, for now. r=dholbert Differential Revision: https://phabricator.services.mozilla.com/D25119

Bug 1558506 - Don't send a message for context menus when we know we don't want to open one. r=NeilDeakin This fixes Bug 1558506 by making it so that the parent process ignores the context menu event when right-clicking on the remote <browser> hosting the Add-on Options page. Before, we were handling the event, stopping it from propagating and preventDefault'ing it, and then sending a message to the parent that ultimately did nothing (since we knew that we didn't want to display the context menu). Stopping propagation and preventDefault'ing meant that the event was never fired in the Extension process for the options page. With the parent process now returning early in the event that it knows that it doesn't want to be the one to open the context menu, the underlying ContextMenuSpecialProcessChild can handle the contextmenu event in the extension process, and do the right thing. Differential Revision: https://phabricator.services.mozilla.com/D34901

Bug 1558996 - Require rust 1.35 r=glandium Differential Revision: https://phabricator.services.mozilla.com/D34794