* Added code snippets for FloatingActionButton Class. ref:#21136

* Extraneous white spaces.
Co-Authored-By: Piinks <katelovett@google.com>

* Alignment correction.

* The analyze result wasn't showing on github interface. Checked through Cirrus and it's all-green.
Co-Authored-By: Piinks <katelovett@google.com>

Use a simpler implementation of Diagnosticable.toString when running in profile/release mode (#28661)

Diagnosticable.toString may be called in performance sensitive contexts
(for example, creating debug labels for Tickers)

This function is called frequently with non-repeating images during many
animations

This change permits
(1) a relative --flutter-shell
(2) relative (source, dill) entries within the test JSON file

and enables portability in the invocation scripts produced by fuchsia's
dart test GN template.

https://github.com/flutter/engine/compare/e9eae9a1af77...4f54a1dd9444

git log e9eae9a1af77400d02c498f0ad943f2858845398..4f54a1dd944497bd1ec0f2acca22ff9fbd8b377a --no-merges --oneline
4f54a1dd9 Roll src/third_party/skia c1a9feb6f06e..5800f2e8a920 (2 commits) (flutter/engine#8022)
75e2b4702 Roll src/third_party/skia c6671be0ea75..c1a9feb6f06e (2 commits) (flutter/engine#8021)
b44a9305c Roll src/third_party/skia 1b9f889628e0..c6671be0ea75 (1 commits) (flutter/engine#8020)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

e9eae9a1a Roll src/third_party/skia c97b0672a73f..1b9f889628e0 (1 commits) (flutter/engine#8019) (#28801)


https://github.com/flutter/engine/compare/a28329cb91ac...e9eae9a1af77

git log a28329cb91ac18ad4d7950b3b170a74a8de979ee..e9eae9a1af77400d02c498f0ad943f2858845398 --no-merges --oneline
e9eae9a1a Roll src/third_party/skia c97b0672a73f..1b9f889628e0 (1 commits) (flutter/engine#8019)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

https://github.com/flutter/engine/compare/39c46dea4b73...a28329cb91ac

git log 39c46dea4b7347a252218aaff5caac5dc2fec8cd..a28329cb91ac18ad4d7950b3b170a74a8de979ee --no-merges --oneline
a28329cb9 Roll src/third_party/skia 58a75383a70b..c97b0672a73f (1 commits) (flutter/engine#8018)
cdc141072 Roll src/third_party/skia 0d7012a80c17..58a75383a70b (1 commits) (flutter/engine#8017)
01d8a1f27 Roll src/third_party/skia c945f0e31a53..0d7012a80c17 (1 commits) (flutter/engine#8016)
75cd4df37 Roll src/third_party/skia 9159c8ef83b2..c945f0e31a53 (1 commits) (flutter/engine#8015)
13064aec8 Add overloads for lookup that lets you specify a bundle (flutter/engine#8007)
130cf77c5 Build engine for iOS on presubmit (flutter/engine#8011)
7234cc463 Roll src/third_party/skia 705e67347962..9159c8ef83b2 (1 commits) (flutter/engine#8014)
8a0b054a4 Roll src/third_party/skia 09198525261a..705e67347962 (7 commits) (flutter/engine#8013)
36cdd2ee6 Roll src/third_party/skia 436d47d5bde9..09198525261a (6 commits) (flutter/engine#8012)
9bef73a1a Roll src/third_party/skia e1f5b644656f..436d47d5bde9 (3 commits) (flutter/engine#8009)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

https://github.com/flutter/engine/compare/66042161eba1...39c46dea4b73

git log 66042161eba17da968800c57ddd2c314cd787abb..39c46dea4b7347a252218aaff5caac5dc2fec8cd --no-merges --oneline
39c46dea4 Revert "Buffer lifecycle in WindowData (#7999)" (flutter/engine#8010)
293cfcaa5 Guard against using Android API not defined in API level 16 & 17 (flutter/engine#8006)
d7e0bc10c Roll src/third_party/skia 71a23d4195d9..e1f5b644656f (8 commits) (flutter/engine#8004)
0b1740171 Buffer lifecycle in WindowData (flutter/engine#7999)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

* Added code snippet for Expanded class. ref:#21136

* Changed the code samples into snippet application samples.

@xster

* Add curve fastInFastOut

* Rename it to slowCenter

* Rename to slowMiddle

* Add continuous test

When we package Flutter, we used to find the "current" tag (which is the version number) by starting at the revision we are building on and looking backwards in time to find the most recent tag. This causes problems on release builds when we failed to tag properly.

This PR makes the packaging script be more strict by requiring the given revision to itself have a tag, but only when we're publishing the result. When we're not publishing the result, it's more lenient, since otherwise we couldn't test packaging on non-release commits.

I also renamed ProcessRunnerException to PreparePackageException, since we were using that exception more generally than just for processes.

66042161e Roll src/third_party/skia 255569187f27..71a23d4195d9 (1 commits) (flutter/engine#8003) (#28731)


https://github.com/flutter/engine/compare/99f3f7a9c246...66042161eba1

git log 99f3f7a9c246f1ebedc6eefd867cde250b370380..66042161eba17da968800c57ddd2c314cd787abb --no-merges --oneline
66042161e Roll src/third_party/skia 255569187f27..71a23d4195d9 (1 commits) (flutter/engine#8003)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

When pub fails, log the %ERRRORLEVEL% to help diagnose the root cause of
the pub failure.

* add trailing commas on list/map/parameters

* add trailing commas on Invocation with nb of arg>1

* add commas for widget containing widgets

* add trailing commas if instantiation contains trailing comma

* revert bad change

flutter/engine@99f3f7a9c Fix incorrect transformation matrix (flutter/engine#8001)
flutter/engine@c88b09710 Roll src/third_party/skia b7b2da871e95..255569187f27 (23 commits) (flutter/engine#8002)
flutter/engine@302e2e9d2 Fix cursor jumping when typing some special characters. (flutter/engine#7964)
flutter/engine@fe15149d1 Android Embedding PR 12: Add lifecycle methods to FlutterActivity. (flutter/engine#7974)
flutter/engine@6145e9046 Android Embedding PR 13: Integrated text input, keyevent input, and some other channel comms in FlutterView. (flutter/engine#7979)

## Description

This moves another 15-20ms from the animation jank of one of our important client to the startup latency. Unfortunately, this is probably not captured in our current benchmarks (presumably some other bottlenecks overshadow this shader compilation in the worst_frame benchmark). Considering that drawing images is such a common operation, maybe we should add one in the future to benchmark this.

We need this PR to land soon for our client because this changes the API to return Future.

## Related Issues

https://github.com/flutter/flutter/issues/813

See https://github.com/flutter/flutter/pull/28614#discussion_r261422778
and https://github.com/flutter/flutter/pull/28614#pullrequestreview-209359908

https://github.com/flutter/engine/compare/5194919e1309...56c16154eada

git log 5194919e130917d29ac15f0ac7f52ea94d1a4d67..56c16154eadada5f77c57ddca39a86c5e30c5768 --no-merges --oneline
56c16154e Android Embedding PR 9: Introduce an AndroidTouchProcessor to convert MotionEvents to Flutter touch data. (flutter/engine#7947)
a1d84996d Fix spelling errors in dartdocs (flutter/engine#7997)
6bc9c3d17 Roll src/third_party/dart 40bab34fbd..7c70ab1817 (35 commits)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

Fix the spelling errors in the dartdocs for the framework.

There are no functionality changes here, just documentation fixes.

One of our important client's SKP shows that this could improve one of
their janky frame by 20ms. This also improves our
flutter_gallery__transition_perf's worst frame time by ~20ms.

On the other hand, 15ms has been added to the start-up latency. I guess
it's a little faster to compile the shader on the start-up because we're
compiling a lot of shaders there and the CPU cache must be hot.

## Related Issues

https://github.com/flutter/flutter/issues/813

https://github.com/flutter/engine/compare/9b924765f4de...5194919e1309

git log 9b924765f4de29cb9751eb598a629f0cc8d4975b..5194919e130917d29ac15f0ac7f52ea94d1a4d67 --no-merges --oneline
5194919e1 Roll src/third_party/skia 1179d5dfaf8d..b7b2da871e95 (1 commits) (flutter/engine#7996)
58ce0fff7 Roll src/third_party/skia 90043480b587..1179d5dfaf8d (3 commits) (flutter/engine#7995)
72cbe69cc Fix two typos in embedder.h (flutter/engine#7993)
2360b459d Android Embedding PR 11: Add FlutterEngine to FlutterFragment. (flutter/engine#7972)
df03ec74f Roll src/third_party/skia 0cedddc1420b..90043480b587 (1 commits) (flutter/engine#7994)
4a148cdc8 Roll src/third_party/skia 67d87128fd00..0cedddc1420b (10 commits) (flutter/engine#7992)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

* Update flat_button.dart

* Added smaple code for Flat Button

* Update flat_button.dart

* Revert "Update flat_button.dart"

This reverts commit c8f00dff39e18b267295890bd0c5a86979b58c24.

* Revert "Added smaple code for Flat Button"

This reverts commit adc4234bc7956293a5b56f39701c6967fe3e919a.

* Update flat_button.dart

* Update flat_button.dart

* Update flat_button.dart

* remove white spaces

* remove white spaces

* add two different samples

* Update flat_button.dart

https://github.com/flutter/engine/compare/3e4e6f5c54db...9b924765f4de

git log 3e4e6f5c54db7a705e6d50f7f3bddfa2ac0d6612..9b924765f4de29cb9751eb598a629f0cc8d4975b --no-merges --oneline
9b924765f Improve performance of Locale.toString (flutter/engine#7990)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.

https://github.com/flutter/engine/compare/4434a39c7d54...3e4e6f5c54db

git log 4434a39c7d545ed47186b2f4d98cd09c8366e720..3e4e6f5c54db7a705e6d50f7f3bddfa2ac0d6612 --no-merges --oneline
3e4e6f5c5 Provide batching for semantics updates (flutter/engine#7988)
0852795bf Roll src/third_party/skia ff84d8a900d4..67d87128fd00 (7 commits) (flutter/engine#7987)
1089b5c9f Check for a null pressure range for motion events (flutter/engine#7986)
b7d512949 [macos] Add hover support to FLEViewController (flutter/engine#7975)
a82c7ee73 Add async events to pipeline flows. (flutter/engine#7985)
c3eb7aea8 Roll src/third_party/skia ab3f8674c9d2..ff84d8a900d4 (1 commits) (flutter/engine#7983)
15793288e Roll src/third_party/dart 9450c6d829..40bab34fbd (8 commits)
b324969c1 Roll src/third_party/dart e94e797d7b..9450c6d829 (8 commits)
3f3e4ec90 Roll src/third_party/skia f6faf2fcea7b..ab3f8674c9d2 (2 commits) (flutter/engine#7980)
d162ad842 Roll src/third_party/skia 4dbb96dfaa04..f6faf2fcea7b (7 commits) (flutter/engine#7977)
5deb15cdf Roll src/third_party/dart 05bba46133..e94e797d7b (5 commits)
4db7c3050 Android Embedding PR 10: Add system channels to FlutterEngine. (flutter/engine#7960)
9f92324fd Suppress deprecation warning for usage of Configuration.locale (flutter/engine#7973)
9b21ea857 Roll src/third_party/dart 385be0cf31..05bba46133 (6 commits)
e3f1bdc4d Roll src/third_party/skia adfc6e40df30..4dbb96dfaa04 (6 commits) (flutter/engine#7970)
e32531f0e Switch flutter's dart sdk to full and add dartdevc libraries (flutter/engine#7968)
fb1c543dd Link dart:* sources into engine for debugger source support (flutter/engine#7908)
dd3656a51 Roll src/third_party/dart 0f9a5198bd..385be0cf31 (14 commits)

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

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

If the roll is causing failures, please contact the current sheriff (garyq@google.com), and stop
the roller if necessary.