Bug 1607537: Fix timeouts in ParentCrashTest.crashParent and re-enable the test; r=geckoview-reviewers,esawin The fundamental issue here is that `ParentCrashTest` starts a second `GeckoRuntime` via `RemoteGeckoService` within the same logical Android Application. This patch adds `RuntimeCreator.shutdownRuntime()` so that the test can shut down the existing `GeckoRuntime` before starting up its own. Differential Revision: https://phabricator.services.mozilla.com/D61249

Bug 1612448. Improve some error messages in accessibility code. r=Jamie Differential Revision: https://phabricator.services.mozilla.com/D61325

Bug 1610416 - Expose SavedFrame frames via debugger server. r=jlast Differential Revision: https://phabricator.services.mozilla.com/D61517

Bug 1610415 - Expose SavedFrame objects from Debugger.Frame. r=arai Differential Revision: https://phabricator.services.mozilla.com/D61425

Bug 1607476 - update expiration for FirstStartup scalars r=chutten Differential Revision: https://phabricator.services.mozilla.com/D60708

Merge mozilla-central to autoland. CLOSED TREE

Bug 1543570 - Make CustomElementConstructor exceptions more consistent; r=smaug See https://github.com/whatwg/html/pull/4525. Differential Revision: https://phabricator.services.mozilla.com/D61247

Bug 1613245 - Prevent getters with side effects from running when update is disable by policy r=mhowell Differential Revision: https://phabricator.services.mozilla.com/D61642

Bug 1611462 - Use DeleteProperty rather than RemoveProperty to avoid leaking. CLOSED TREE MANUAL PUSH: LSAN failures.

No bug: [mozharness] Stop removing old dist packages; r=nalexander Every build is a clobber, so we don't need to clean things up at the beginning of a build. Differential Revision: https://phabricator.services.mozilla.com/D61608

No bug: Remove knowledge of buildid from mozharness; r=nalexander Mozharness currently deals with buildid in two places: - It passes `MOZ_BUILD_DATE` through the environment in a complicated way, and sets it if it isn't set. - It verifies that the buildid of the generated package matches that the one it determined. The former is duplicate code, and the later requires knowing details of the build for little value. Differential Revision: https://phabricator.services.mozilla.com/D61607

Bug 1612206 - Ensure maybeReloadEngines is scheduled r=Standard8 Differential Revision: https://phabricator.services.mozilla.com/D61244

Bug 1612401 - Prevent absolute-positioned children from contributing gap size to flexbox's inline-size. r=dholbert Differential Revision: https://phabricator.services.mozilla.com/D61622

Bug 1613209 - Allow clang-plugin on arm64-windows r=froydnj I'm guessing that maybe this was a leftover from when we built arm64-windows with MSVC. In any case, the plugin seems to work fine now. Differential Revision: https://phabricator.services.mozilla.com/D61620

Bug 1230378 - Add a crashtest. r=mats Differential Revision: https://phabricator.services.mozilla.com/D61593

Bug 1612510 - Remove IsChromeOrXBL*. r=bzbarsky XBL is no longer a thing... Also, should we rename AllowContentXBLScope? Differential Revision: https://phabricator.services.mozilla.com/D61359

Bug 1612470 - Remove Document.hasScriptsBlockedBySandbox and Document.inlineScriptAllowedByCSP. r=bzbarsky Seems they were only used for the old XBL marquee implementation and have no remaining callers. Differential Revision: https://phabricator.services.mozilla.com/D61338

Bug 1611462 - Optimize position changes better. r=dholbert When our position changes from / to absolute / fixed, then we need to reframe (most likely, at least). But in some easier cases we can just live with a reflow plus (optionally) a containing-block update or a repaint, depending on the case. We need to delete the normal position property when this happens and we switch from static to relative/sticky, and also need to update the handling of UpdateContainingBlock to avoid making decisions based on position not changing. This will actually not cause more reframes, as one would expect, because that optimization became somewhat obsolete by bug 1519371 (which made the optimization exact). Differential Revision: https://phabricator.services.mozilla.com/D61142

Bug 1596285 - Mark most test suites tier 2 for ccov. r=aryx Differential Revision: https://phabricator.services.mozilla.com/D58919

Bug 1613114 - Remove rounding the backdrop filter bounds during WR display list building. r=jrmuizel No other items need to round their bounds/clips, and backdrop filters should be no exception. They should trust scene building (and to a lesser extent, frame building) to perform any necessary snapping. This patch also removes the ToRoundedLayoutPoint/Rect methods as there are no more users of the APIs, nor should there ever be. Differential Revision: https://phabricator.services.mozilla.com/D61618