Syncs the BUILD.gn with pubspec.yaml for package:test. This fixes a
breakage in the Fuchsia tree.

* Update CONTRIBUTING.md

* Update CONTRIBUTING.md

ca86f6d7e Roll src/third_party/skia 52a6a40535b0..b081bc4a3139 (4 commits) (flutter/engine#11267) (#38911)


git@github.com:flutter/engine.git/compare/d212b9ab33a0...ca86f6d7e153

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2019-08-20 skia-flutter-autoroll@skia.org Roll src/third_party/skia 52a6a40535b0..b081bc4a3139 (4 commits) (flutter/engine#11267)

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2019-08-20 bkonyi@google.com Revert "Roll src/third_party/dart f7902889b6..6e2b3f0326 (7 commits)" (flutter/engine#11298)
2019-08-20 bkonyi@google.com Revert "Roll src/third_party/dart 6e2b3f0326..b99df2be86 (5 commits) (#11287)" (flutter/engine#11297)
2019-08-20 bkonyi@google.com Roll src/third_party/dart 6e2b3f0326..b99df2be86 (5 commits) (flutter/engine#11287)
2019-08-20 bkonyi@google.com Roll src/third_party/dart f7902889b6..6e2b3f0326 (7 commits)

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cc @gspencergoog

For https://github.com/flutter/flutter/issues/36064

That performance regression is iOS-only so we'd better get the
benchmarks running on iOS.

Flutter widget tests assert if a test completes with timers still
pending.  However, it can be hard to diagnose where a pending timer
came from.  For example, a widget might consume a third-party library
that internally uses a timer.

I added a FakeAsync.pendingTimersDebugInfo getter to quiver
(https://github.com/google/quiver-dart/pull/500).  Make flutter_test
use it.

Additionally modify Flutter's debugPrintStack to take an optional
StackTrace argument instead of always printing StackTrace.current.

Fixes #4237.

* Add ToggleButtons.textStyle property

Switch from the un-suffixed Windows and Linux libraries to the
_glfw-suffixed versions, in preparation for having non-GLFW versions
using the previous library/wrapper names.

Part of #38589

10167db43 Roll src/third_party/skia 5f152f07455c..52a6a40535b0 (1 commits) (flutter/engine#11253) (#38874)


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2019-08-20 skia-flutter-autoroll@skia.org Roll src/third_party/skia 5f152f07455c..52a6a40535b0 (1 commits) (flutter/engine#11253)

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2019-08-20 bkonyi@google.com Roll src/third_party/dart 9f13d07670..f7902889b6 (3 commits)

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df178fd93 Remove dart entrypoint Intent parameter from FlutterActivity. (#38713) (flutter/engine#11239) (#38867)


git@github.com:flutter/engine.git/compare/f4591a73a5c7...df178fd936c0

git log f4591a73a5c7..df178fd936c0 --no-merges --oneline
2019-08-20 matthew-carroll@users.noreply.github.com Remove dart entrypoint Intent parameter from FlutterActivity. (#38713) (flutter/engine#11239)

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2019-08-19 skia-flutter-autoroll@skia.org Roll src/third_party/skia 8566dda51b42..5f152f07455c (8 commits) (flutter/engine#11241)
2019-08-19 chinmaygarde@google.com Provide a placeholder queue ID for the custom embedder task runner. (flutter/engine#11062)

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2019-08-19 bkonyi@google.com Roll src/third_party/dart 0e201edeeb..9f13d07670 (27 commits)
2019-08-19 matthew-carroll@users.noreply.github.com Notify framework to clear input connection when app is backgrounded (#35054) (flutter/engine#9498)
2019-08-19 dnfield@google.com Re-enable firebase test and don't use google login (flutter/engine#11228)
2019-08-19 ariaye@google.com Update tflite_native and language_model revisions to match the Dart SDK (flutter/engine#11230)
2019-08-19 skia-flutter-autoroll@skia.org Roll src/third_party/skia f8221786d088..8566dda51b42 (4 commits) (flutter/engine#11220)
2019-08-19 chinmaygarde@google.com Update metal layer drawable size on relayout. (flutter/engine#11224)
2019-08-19 dnfield@google.com Make firebase testlab always pass (flutter/engine#11226)

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* Added new ButtonBarTheme to replace the deprecated ButtonTheme.bar method.

* Responding to PR feedback.

* [Material] Create material Banner component (#36880)

This PR creates a new material widget for the Banner component. This includes a theme as well. This widget can be dropped into any application, ideally at the top of a listview or scrollview.

(cherry picked from commit 35b6d668)

Removed the use of ButtonTheme.bar in the Banner implementation.

* Updated documentation from PR review comments.

Filed: https://github.com/flutter/flutter/issues/38838
to track these usages.

This was introduced by: https://github.com/flutter/engine/pull/11041

* 19327c8b7 Show all license diffs (flutter/engine#11034)

* e97ed36e5 Add a BroadcastStream to FrameTiming (flutter/engine#11041)

* 21ae92651 [b/139487101] Dont present session twice (flutter/engine#11222)

7292d47e6 Roll src/third_party/skia 9648b419f5cf..f8221786d088 (1 commits) (flutter/engine#11206) (#38809)


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2019-08-19 skia-flutter-autoroll@skia.org Roll src/third_party/skia 9648b419f5cf..f8221786d088 (1 commits) (flutter/engine#11206)

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This reverts commit 8edc3f76.

git@github.com:flutter/engine.git/compare/6c843b4dd22e...20b4ec7552af

git log 6c843b4dd22e..20b4ec7552af --no-merges --oneline
2019-08-19 bkonyi@google.com Roll src/third_party/dart 9c649e67df..0e201edeeb (2 commits)

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