This updated the broken android_semantics_test to correspond to existing engine behavior.

This adds a Semantics node to the Focus and FocusScope widgets, setting the focused and focusable attributes so that the accessibility subsystem can be told when a control has the input focus.

Includes an engine roll to flutter/engine@77252d2, and the following 8 engine changes:

flutter/engine@77252d2 Greg Spencer Add missing focusable testing info (flutter/engine#13013)
flutter/engine@0e42a29 skia-flutter-.. Roll src/third_party/skia 54548626a977..e27a503a0a21 (1 commits) (flutter/engine#13024)
flutter/engine@6b56ed7 gaaclarke Refactor: FlutterDartProject (flutter/engine#13006)
flutter/engine@393480c skia-flutter-.. Roll src/third_party/skia 77dde599c98a..54548626a977 (1 commits) (flutter/engine#13023)
flutter/engine@080b89d skia-flutter-.. Roll src/third_party/skia 2b1a25a4d324..77dde599c98a (1 commits) (flutter/engine#13021)
flutter/engine@90b0f30 Ben Konyi Roll src/third_party/dart f4a72bfc64..bb04f145b2 (18 commits) (flutter/engine#13020)
flutter/engine@049fb89 skia-flutter-.. Roll fuchsia/sdk/core/linux-amd64 from q_uYX... to cknsi... (flutter/engine#13019)
flutter/engine@6925b2a skia-flutter-.. Roll fuchsia/sdk/core/mac-amd64 from wuAtw... to u0JpE... (flutter/engine#13018)

Related Issues
Addresses #40101

Landing on red in order to fix the build: it's red because of the needed engine roll.

Fix regression with ModalBottomSheets not responding to changes in theme
after they are shown.

0d749933b Roll src/third_party/skia 1494a7f1ec03..2b1a25a4d324 (15 commits) (flutter/engine#13016) (#42290)


git@github.com:flutter/engine.git/compare/1e58794b238b...0d749933bcc6

git log 1e58794b238b..0d749933bcc6 --no-merges --oneline
2019-10-09 skia-flutter-autoroll@skia.org Roll src/third_party/skia 1494a7f1ec03..2b1a25a4d324 (15 commits) (flutter/engine#13016)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

Ensure web restart analytics events aren't sent for failures/dont serve devtools by default  (#42260)

git@github.com:flutter/engine.git/compare/21b8224ae12d...1e58794b238b

git log 21b8224ae12d..1e58794b238b --no-merges --oneline
2019-10-09 chinmaygarde@gmail.com Revert "Upgrade compiler to Clang 10. (#11256)" (flutter/engine#13017)
2019-10-09 chinmaygarde@google.com Upgrade compiler to Clang 10. (flutter/engine#11256)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
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Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

git@github.com:flutter/engine.git/compare/c635d70c7266...21b8224ae12d

git log c635d70c7266..21b8224ae12d --no-merges --oneline
2019-10-08 gspencergoog@users.noreply.github.com Send AccessibilityEvent.TYPE_VIEW_FOCUSED when input focus is set. (flutter/engine#12746)
2019-10-08 dnfield@google.com Fix for a11y crash on iOS (flutter/engine#12990)
2019-10-08 katelovett@google.com Link Semantics Typo (flutter/engine#13009)
2019-10-08 ferhat@gmail.com [web] Add support for path transform (flutter/engine#12794)
2019-10-08 jason-simmons@users.noreply.github.com Auto-formatter fixes for BUILD.gn files (flutter/engine#13005)
2019-10-08 bkonyi@google.com Unblock SIGPROF on flutter_tester start (flutter/engine#12813)
2019-10-08 mouad.debbar@gmail.com [web] Update the url when route is replaced (flutter/engine#13003)
2019-10-08 katelovett@google.com Missing link flag (flutter/engine#13001)
2019-10-08 30870216+gaaclarke@users.noreply.github.com Started setting our debug background task id to invalid after completion. (flutter/engine#12999)
2019-10-08 ychris@google.com Add `onUnregistered` callback in 'Texture' and 'FlutterTexture' (flutter/engine#12695)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

git@github.com:flutter/engine.git/compare/5b3182294f63...c635d70c7266

git log 5b3182294f63..c635d70c7266 --no-merges --oneline
2019-10-08 skia-flutter-autoroll@skia.org Roll src/third_party/skia 902cf1e12a74..1494a7f1ec03 (10 commits) (flutter/engine#13000)
2019-10-08 liyuqian@google.com SkSL precompile (flutter/engine#12412)
2019-10-08 chinmaygarde@google.com Compile sanitizer suppressions list and file bugs as necessary. (flutter/engine#12991)
2019-10-08 chinmaygarde@google.com Add a unit-test to verify that root surface transformation affect platform view coordinates. (flutter/engine#12783)
2019-10-08 katelovett@google.com Re-land Adding Link Semantics (flutter/engine#12972)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

git@github.com:flutter/engine.git/compare/3a445edda924...5b3182294f63

git log 3a445edda924..5b3182294f63 --no-merges --oneline
2019-10-08 bkonyi@google.com Roll src/third_party/dart aece1c1e92..f4a72bfc64 (4 commits)
2019-10-08 30870216+gaaclarke@users.noreply.github.com Added an embedder example (flutter/engine#12808)
2019-10-08 sebastian.roth@gmail.com Fix typo on channel buffer debug output. (flutter/engine#12960)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

git@github.com:flutter/engine.git/compare/49dbaae818cd...3a445edda924

git log 49dbaae818cd..3a445edda924 --no-merges --oneline
2019-10-08 30870216+gaaclarke@users.noreply.github.com Made _printDebug only happen on debug builds of the engine for now. (flutter/engine#12980)
2019-10-08 devoncarew@google.com remove references to package:_chrome (flutter/engine#12931)
2019-10-08 ditman@gmail.com Open source canvas tests from flutter_web_ui (flutter/engine#12819)
2019-10-08 mouad.debbar@gmail.com Prevent default when Tab is clicked (flutter/engine#12986)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

git@github.com:flutter/engine.git/compare/611c345a4e76...49dbaae818cd

git log 611c345a4e76..49dbaae818cd --no-merges --oneline
2019-10-08 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/linux-amd64 from gB_ii... to q_uYX... (flutter/engine#12996)
2019-10-08 aam@google.com Roll dart to aece1c1e92. (flutter/engine#12997)
2019-10-08 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from wOfz2... to wuAtw... (flutter/engine#12995)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

Similar to errorMaxLines

611c345a4 Roll src/third_party/skia a28cf7c08061..902cf1e12a74 (4 commits) (flutter/engine#12994) (#42244)


git@github.com:flutter/engine.git/compare/819b0cae0c23...611c345a4e76

git log 819b0cae0c23..611c345a4e76 --no-merges --oneline
2019-10-08 skia-flutter-autoroll@skia.org Roll src/third_party/skia a28cf7c08061..902cf1e12a74 (4 commits) (flutter/engine#12994)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

git@github.com:flutter/engine.git/compare/4a849e0f8dd5...819b0cae0c23

git log 4a849e0f8dd5..819b0cae0c23 --no-merges --oneline
2019-10-08 skia-flutter-autoroll@skia.org Roll src/third_party/skia f611d943fb73..a28cf7c08061 (29 commits) (flutter/engine#12993)
2019-10-08 garyq@google.com Unpublicize kDoNotResizeDimension (flutter/engine#12989)
2019-10-08 skia-flutter-autoroll@skia.org Roll src/third_party/skia 4c82a9fc83a5..f611d943fb73 (1 commits) (flutter/engine#12831)
2019-10-08 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from kwa2O... to wOfz2... (flutter/engine#12827)
2019-10-08 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/linux-amd64 from by2LL... to gB_ii... (flutter/engine#12979)
2019-10-08 jason-simmons@users.noreply.github.com Roll Wuffs to 0.2.0-rc.1 (flutter/engine#12983)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

git@github.com:flutter/engine.git/compare/1d62160fdb2f...4a849e0f8dd5

git log 1d62160fdb2f..4a849e0f8dd5 --no-merges --oneline
2019-10-08 dnfield@google.com Color matrix doc (flutter/engine#12982)
2019-10-07 jason-simmons@users.noreply.github.com Use the standard gen_snapshot target unless the platform requires host_targeting_host (flutter/engine#12988)
2019-10-07 bkonyi@google.com Roll src/third_party/dart 8413a0db0d..8ba6f7e2eb (39 commits) (flutter/engine#12981)
2019-10-07 liyuqian@google.com Unblock Fuchsia roll (flutter/engine#12977)
2019-10-06 chinmaygarde@google.com Update buildroot to pull in ubsan updates. (flutter/engine#12821)
2019-10-05 skia-flutter-autoroll@skia.org Roll src/third_party/skia 95edac1c9a4a..4c82a9fc83a5 (13 commits) (flutter/engine#12818)
2019-10-05 chinmaygarde@google.com Enable sanitizer build variants. (flutter/engine#12816)
2019-10-05 katelovett@google.com Revert "Adding Link SemanticsFlag (#12453)" (flutter/engine#12815)
2019-10-04 jason-simmons@users.noreply.github.com Use the x64 host toolchain for x86 target gen_snapshot only on Linux (flutter/engine#12809)
2019-10-04 yjbanov@google.com add option for bulk-updating screenshots; update screenshots (flutter/engine#12797)
2019-10-04 dnfield@google.com unbreak unopt fuchsia (flutter/engine#12805)
2019-10-04 jason-simmons@users.noreply.github.com Build gen_snapshot with a 64-bit host toolchain even if the target platform is 32-bit (flutter/engine#12802)
2019-10-04 dnfield@google.com [flutter_runner] a11y updates, tests! (flutter/engine#12380)
2019-10-04 WATER1350@gmail.com Fix crash in copypixelbuffer (flutter/engine#10326)
2019-10-04 bkonyi@google.com Roll src/third_party/dart d6c6d12ebf..8413a0db0d (2 commits)
2019-10-04 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from JyZWz... to kwa2O... (flutter/engine#12803)
2019-10-04 katelovett@google.com Adding Link SemanticsFlag (flutter/engine#12453)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC liyuqian@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

Applying our style guide:
https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo#have-good-hygiene-when-using-temporary-directories

Add more web tests;use blacklist instead of whitelist

The Material Dark Theme spec has been updated (or soon will be) to clarify that the elevation overlay that is applied to surface colors to indicate elevation should be based off of the colorScheme.onSurface color and not white. This commit implements this change.

Reland "AOT support for Linux Desktop I: switch Linux builds to assemble (#41612)" (#42030)" (#42038)

This reverts commit 142a8630.

git@github.com:flutter/engine.git/compare/7d90779bb66f...1d62160fdb2f

git log 7d90779bb66f..1d62160fdb2f --no-merges --oneline
2019-10-04 iska.kaushik@gmail.com Prettify all CMX files (flutter/engine#12800)
2019-10-04 garyq@google.com Restart all modern Samsung keyboard IMM (flutter/engine#12780)
2019-10-04 dnfield@google.com Reland fuchsia build improvements (flutter/engine#12795)
2019-10-04 50856934+nturgut@users.noreply.github.com Fixing selection issues in Firefox (flutter/engine#12793)
2019-10-04 chinmaygarde@google.com Disable EmbedderTest::CanLaunchAndShutdownMultipleTimes. (flutter/engine#12799)
2019-10-04 iska.kaushik@gmail.com [flutter_runner] Update the cmx files to include TZ support (flutter/engine#12798)
2019-10-04 skia-flutter-autoroll@skia.org Roll src/third_party/skia fbdf48ecb204..95edac1c9a4a (1 commits) (flutter/engine#12790)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC liyuqian@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md