* Add clarifying docs on MaterialButton.colorBrightness

FocusTraversalPolicy keep the previously visited node to avoid hysteresis. But even if the visited focus has been disposed, FocusTraversalPolicy will still use it to requestFocus, which will cause FocusManger to get an abandoned node to get the focus.

This reverts commit 39baa099.

Update `FakeHttpClientResponse` to be impervious to Dart SDK
changes to the `HttpClientResponse` stream type (between `List<int>`
and `Uint8List`).

This PR created a main page for platform view tests in the android views testing app. The main page none contains a list of the links to the pages being tested. It puts the android view motion events tests to a sub page.
The PR also added iOS related files to get ready for adding the iOS platform views tests.

eb248c242 Roll src/third_party/skia 14b5e6bb8fcf..63fdd0191be0 (2 commits) (flutter/engine#9880) (#36361)


https://github.com/flutter/engine/compare/00acf2a18065...eb248c242574

git log 00acf2a180651cbf1e480316d7d64af8a62dcf47..eb248c242574e8f7f4d4b4532b6db21dfbe1a5a0 --no-merges --oneline
eb248c242 Roll src/third_party/skia 14b5e6bb8fcf..63fdd0191be0 (2 commits) (flutter/engine#9880)

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00acf2a18 Roll fuchsia/sdk/core/mac-amd64 from w823y-1sH6L6jGXwMOrVkgZMGP2zpKnNUzyvshzPlFMC to f97PVV8BR3sa4rxRIc-xgvBxd6HYa8mKNp8zGmqqx-UC (flutter/engine#9879) (#36357)


https://github.com/flutter/engine/compare/98241b7b05aa...00acf2a18065

git log 98241b7b05aa605755dc87ce33c7f6fb189d4863..00acf2a180651cbf1e480316d7d64af8a62dcf47 --no-merges --oneline
00acf2a18 Roll fuchsia/sdk/core/mac-amd64 from w823y-1sH6L6jGXwMOrVkgZMGP2zpKnNUzyvshzPlFMC to f97PVV8BR3sa4rxRIc-xgvBxd6HYa8mKNp8zGmqqx-UC (flutter/engine#9879)

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https://github.com/flutter/engine/compare/f336286cde9c...98241b7b05aa

git log f336286cde9c17d4aa36e3217f91cc0b239a3391..98241b7b05aa605755dc87ce33c7f6fb189d4863 --no-merges --oneline
98241b7b0 Roll src/third_party/skia 08ba11370342..14b5e6bb8fcf (3 commits) (flutter/engine#9874)
d4cb3e6e4 Roll fuchsia/sdk/core/mac-amd64 from xJPmd7maxxcPRu9HpByelwYaqa-v6qipCfy6JhgYS9oC to w823y-1sH6L6jGXwMOrVkgZMGP2zpKnNUzyvshzPlFMC (flutter/engine#9871)
4f307785f Update buildroot to pick up Fuchsia artifact roller. (flutter/engine#9866)

The AutoRoll server is located here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll

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If the roll is causing failures, please contact the current sheriff (aaclarke@google.com), and stop
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https://github.com/flutter/engine/compare/e3e4b26fce0d...f336286cde9c

git log e3e4b26fce0de9d4aa870835ffad24e6817a08ce..f336286cde9c17d4aa36e3217f91cc0b239a3391 --no-merges --oneline
f336286cd Roll src/third_party/skia 947efe28de74..08ba11370342 (9 commits) (flutter/engine#9865)
dcac8a9c9 Fixed error in generated xml Info.plist. (flutter/engine#9867)
b7e5940e3  Started adding the engine hash to frameworks' Info.plist. (flutter/engine#9847)

The AutoRoll server is located here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll

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https://github.com/flutter/engine/compare/66092d5b02dc...e3e4b26fce0d

git log 66092d5b02dcaf627295c5d5333956ebc82ad53b..e3e4b26fce0de9d4aa870835ffad24e6817a08ce --no-merges --oneline
e3e4b26fc Roll fuchsia/sdk/core/mac-amd64 from pwsYtqWGHRP43dB0EyLu7S9R3uGV0dIhulPbnSUDUmcC to xJPmd7maxxcPRu9HpByelwYaqa-v6qipCfy6JhgYS9oC (flutter/engine#9858)
3233f9422 Disable Fuchsia Debug & Release presubmits and only attempt the Profile unopt variant. (flutter/engine#9856)
6e1a3e812 Roll src/third_party/skia a3e2996b0834..947efe28de74 (6 commits) (flutter/engine#9853)
9eed783e9 Selectively enable tests that work on Windows and file issues for ones that don't. (flutter/engine#9852)
7ae3c3e11 Preserve the alpha for VD content by setting a transparent background. (flutter/engine#9849)
a3926a3c6 Roll fuchsia/sdk/core/mac-amd64 from 94o0_NIcwi-V68SmUN4hU0fX5_JkMpPU5V8HaFvKWfYC to pwsYtqWGHRP43dB0EyLu7S9R3uGV0dIhulPbnSUDUmcC (flutter/engine#9848)

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https://github.com/flutter/engine/compare/b25a1a406d0b...66092d5b02dc

git log b25a1a406d0b01b445be7dbaeac1741324949b25..66092d5b02dcaf627295c5d5333956ebc82ad53b --no-merges --oneline
66092d5b0 SendPlatformMessage allow null message value (flutter/engine#9781)
69cacb5fc Roll src/third_party/skia 0902c98825bf..a3e2996b0834 (8 commits) (flutter/engine#9846)
5c7c7c491 Roll fuchsia/sdk/core/mac-amd64 from IM-VITwgPUQ_cIbDBZHl9u_M_LPgWjLdnr7EM94udkoC to 94o0_NIcwi-V68SmUN4hU0fX5_JkMpPU5V8HaFvKWfYC (flutter/engine#9845)
a0f5eb144 Roll src/third_party/skia c8e8e7061f1e..0902c98825bf (1 commits) (flutter/engine#9844)
1a571b0e5 Roll fuchsia/sdk/core/mac-amd64 from AsA8eYRT0BzzdU2_dr5qJJjqzVRO2wdUzp4eNyMfCmgC to IM-VITwgPUQ_cIbDBZHl9u_M_LPgWjLdnr7EM94udkoC (flutter/engine#9843)
64b6fc5a7 Roll fuchsia/sdk/core/mac-amd64 from t2vViX8EgEJz6fl_09azrb6Lr5qzlxA5I7NGADwIPmsC to AsA8eYRT0BzzdU2_dr5qJJjqzVRO2wdUzp4eNyMfCmgC (flutter/engine#9842)
7e8b4b559 Roll src/third_party/skia d830fd98a4ef..c8e8e7061f1e (4 commits) (flutter/engine#9841)
1574c49ac Roll fuchsia/clang/mac-amd64 from Lc64-GTi4kihzkCnW8Vaa80TWTnMpZY0Fy6AqChmqvcC to USm3Qt9wen4bXoFF0T9Xt8NX-pyEfte2cTYi7geLAhQC (flutter/engine#9838)
4025cff81 Roll fuchsia/clang/linux-amd64 from oEsFSe99FkcDKVxZkAY0MKi6C-yYOan1m-QL45N33W8C to apsjZJ9ZIwlS08divc0QwxuNgIFeN4X-52mKR9d8qacC (flutter/engine#9839)
0a35db771 Roll src/third_party/skia 8ab6160c8149..d830fd98a4ef (3 commits) (flutter/engine#9836)

The AutoRoll server is located here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll

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Slight cleanup of file locations in flutter_tools
to make it easier to see which files are responsible
for data reporting.

This reverts commit 5501a1c1.

Added support for a semi-transparent white overlay color for `Material` widgets to indicate their elevation in a dart theme. A new `ThemeData.applyElevationOverlayColor` flag was added to control this behavior, which is off by default for backwards compatibility reasons.

## Description

Instead of detaching from the spawned App process on the device immediately, keep the LLDB client connection open (in autopilot mode) until the App quits or the server connection is lost.

This replicates the behavior of Xcode, which also keeps a debugger attached to the App after launching it.

## Tests

This change will be covered by all running benchmarks (which are launched via "flutter run"/"flutter drive"), and probably be covered by all tests as well.

I also tested the workflow locally -- including cases where the App or Flutter CLI is terminated first.

## Breaking Change

I don't believe this should introduce any breaking changes. The LLDB client automatically exits when the app dies or the device is disconnected, so there shouldn't even be any user-visible changes to the behavior of the tool (besides the output of "-v").

Fixes https://github.com/flutter/flutter/issues/36091.

Previously, a sendRequest will be sent even if the peer is closed during
a driver test. That will cause a time out without any error information.
Such issue is unreproducible on my Mac Book Pro, but 100% reproducible
on our new Mac mini (2018).

The closing issue is tracked in https://github.com/flutter/flutter/issues/36268

Additional to this fix, we should also patch the jason_rpc_2 so the peer
will throw exception if sendRequest is attempted while the connection is
closed.

**Test**:
tiles_scroll_perf_iphonexs__timeline_summary failed without this patch.
It will pass after this patch.

I'm not sure how to add a unit test for this. Please let me know if you have
some ideas.

This patch will generate the following warning log on the new Mac Mini
```
flutter: Observatory listening on http://127.0.0.1:50192/cZPDF4sW7MM=/  
Installing and launching...                                        10.2s
00:00 +0: scrolling performance test (setUpAll)
[info ] FlutterDriver: Connecting to Flutter application at http://127.0.0.1:1069/cZPDF4sW7MM=/
[trace] FlutterDriver: Isolate found with number: 3684677742843303
[trace] FlutterDriver: Isolate is paused at start.
[trace] FlutterDriver: Attempting to resume isolate
[trace] FlutterDriver: Waiting for service extension
[info ] FlutterDriver: Connected to Flutter application.
00:00 +0: scrolling performance test complex_layout_scroll_perf
[warning] FlutterDriver: Instance of '_WebSocketImpl' is closed with an unexpected code 1005
[warning] FlutterDriver: Peer connection is closed! Trying to restore the connection...
00:10 +1: scrolling performance test tiles_scroll_perf
[warning] FlutterDriver: Instance of '_WebSocketImpl' is closed with an unexpected code 1005
[warning] FlutterDriver: Peer connection is closed! Trying to restore the connection...
00:20 +2: scrolling performance test (tearDownAll)
00:20 +2: All tests passed!
Stopping application instance.
```

https://github.com/flutter/engine/compare/3f27c5724c1d...74af88ba9f8b

git log 3f27c5724c1d92c14f8353419dfc6cb40a063aa2..74af88ba9f8bb7437edd128ad0eb1926bd2c1ee4 --no-merges --oneline
74af88ba9 Make the virtual display's window translucent (flutter/engine#9828)
bf91bdb8b Roll src/third_party/skia 563d044c0e76..9d844d8ce5a2 (10 commits) (flutter/engine#9831)

The AutoRoll server is located here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll

Documentation for the AutoRoller is here:
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If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
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https://github.com/flutter/engine/compare/76a91d39b4b2...3f27c5724c1d

git log 76a91d39b4b256ef95170ed2d93fccca3c0a0d49..3f27c5724c1d92c14f8353419dfc6cb40a063aa2 --no-merges --oneline
3f27c5724 Roll fuchsia/sdk/core/mac-amd64 from pU_n3ahOhH6HJhE4vs5pUR8cg5U22TItP_Ds_N2OXPIC to qFyiJ56_6XZ5fjNssdCk_vOtBHg4YdWAPNeMIAf07-gC (flutter/engine#9830)
eb4793abf Revert "Roll src/third_party/dart 24725a8559..cbaf890f88 (33 commits) (#9826)" (flutter/engine#9829)
9c54621fd bitcode (flutter/engine#9823)
e105a8982 Roll src/third_party/dart 24725a8559..cbaf890f88 (33 commits) (flutter/engine#9826)
2e83c4a35 Roll fuchsia/sdk/core/linux-amd64 from ehWVT9QJbC-vFMM6SkkQM9HJ9oITFCws7FC9JnrFq2gC to IPgI5Uh4rIZ4zNfAV1_ynC4dGmFLexAW1L9czHUyjowC (flutter/engine#9827)
418fe5b2d Document FontFeature class (flutter/engine#9808)

The AutoRoll server is located here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll

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https://github.com/flutter/engine/compare/919e3532368f...76a91d39b4b2

git log 919e3532368fa1924614272b8dc88874c603fcff..76a91d39b4b256ef95170ed2d93fccca3c0a0d49 --no-merges --oneline
76a91d39b Roll src/third_party/skia 8590026dbf0d..563d044c0e76 (38 commits) (flutter/engine#9824)
8143845b7 Roll fuchsia/sdk/core/mac-amd64 from olF8ZjlM3lWSmWq8XyfXTKoPveuZtTcrGJINk_ERHhwC to pU_n3ahOhH6HJhE4vs5pUR8cg5U22TItP_Ds_N2OXPIC (flutter/engine#9820)
379028ab6 Add the functionality to merge and unmerge MessageLoopTaskQueues (flutter/engine#9436)
8abe85bb9 Revert "Roll src/third_party/dart 24725a8559..28f95fcd24 (32 commits)" (flutter/engine#9817)
96746bc66 Roll src/third_party/skia c3f28e3cf0d4..8590026dbf0d (2 commits) (flutter/engine#9805)
3652a68eb Roll fuchsia/sdk/core/mac-amd64 from CDbRdGJ3bu-aWMCZqN5VzfQqIBwDGL2wfFodWABKdCIC to olF8ZjlM3lWSmWq8XyfXTKoPveuZtTcrGJINk_ERHhwC (flutter/engine#9803)
67d284d45 Roll src/third_party/dart 24725a8559..28f95fcd24 (32 commits)

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This updates the flutter tool cache to download binary files for ideviceinstaller, ios-deploy, libimobiledevice, and dynamically linked dependencies from Flutter's GCP bucket.

Move tools tests into a general.shard directory in preparation to changing how we shard tools tests (#36108)

https://github.com/flutter/engine/compare/d1dcd1848633...919e3532368f

git log d1dcd1848633c5764e23313823445cbcba451a59..919e3532368fa1924614272b8dc88874c603fcff --no-merges --oneline
919e35323 Only release the image data in the unit-test once Skia has accepted ownership of it. (flutter/engine#9816)
b42450f2b Document //flutter/shell/common/engine. (flutter/engine#9769)
f3edc41e6 Update buildroot to c4df4a7b to pull in MSVC 2017 Update 9 on Windows. (flutter/engine#9799)

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