* Added sample code for BottomNavigationBar widget [#21136]

* bottomnavigationbaritems made single line

* Fix form field validate method being called if form field is disabled

Behavior remains the same for multiline TextFields. This behavior already happens on iOS and Android, but not desktop. #23014

* Make it easier to Add2App for iOS

* Use local engine if xcconfig says so

* newline

* fix Curves.bounceInOut

* assert maximum slope

* Future<void> main

* Future<void>.delayed

* prefer_void_to_Null

* address review comments

This reverts commit a34488dd.

aed6b8c46 Roll Dart to ac6d4f7e653deba11d4836768376537893a9e9d6. (#6549)
3ba6270b2 Roll src/third_party/skia 921ec976556c..4b7b2ceb4ad9 (14 commits) (#6550)

This reverts commit c689c97d.

The Dart analyzer in Google3 has been upgraded so we won't need this.

* add onLongPressUp geasture which is fired when a long-press ends

If `items` or `onChanged` is null the button will be disabled, the down arrow will be grayed out, and
the new `disabledHint` will be shown (if provided).

Before this PR AndroidView's gestureRecognizers field was a list of
gesture recognizers. This was problematic as when the widget was rebuilt
with the same gesture recognizer instances we would try to re-join the
recognizers to a gesture arena team and crash (as a OneSeqeunceGestureRecognizer
team can only be set once).

With this change, we instead take a set of factories.
This allows AndroidView to create the gesture recognizers just before
adding them to the team, and thus be sure that they are only added once to a
team.

The factories are identified by the type of the object they create, this
allows AndroidView to know when it is given an equivalent set of gesture
recognizer factories, and do nothing in that case.

https://github.com/flutter/engine/compare/32f417db0d56...08272ee6aa33

git log 32f417db0d56..08272ee6aa33 --no-merges --oneline
08272ee6a Allow specifying custom toolchains and sysroots for host builds. (flutter/engine#6548)
c6456570a Roll src/third_party/skia c6a17104ad68..921ec976556c (31 commits) (flutter/engine#6546)


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This reverts commit bf92d7f2.

* Add support for shadows in text.

* Use dart:ui Shadow as base class for Shadows

* Update lerp definition

* Roll engine 3ffa3629523..84fe4a9f7e24e4 - Text Shadows and update goldens for skia roll.

git log 50c2e69daff4e207c54e463d2304139985c7511c..32f417db0d566d354605305cb29c251276fa65ee --oneline --no-merges
32f417db0 Roll tonic to 077be256142ede39a271385907faadf4fcc62a4d. (#6541)
4ee77256c Revert "Roll Dart to 1f4dfce179c8f05c9e48759300a15e671b88cc10 (#6515)" (#6537)
964acafeb Roll src/third_party/skia 646d917d3c71..c6a17104ad68 (1 commits) (#6536)
d4bae4ca4 Roll src/third_party/skia 2b2c00f6ec36..646d917d3c71 (1 commits) (#6535)
ff93ccf47 Roll src/third_party/skia 681692726fc0..2b2c00f6ec36 (1 commits) (#6534)
a4161c895 Roll src/third_party/skia 23775a2e9736..681692726fc0 (1 commits) (#6532)
116072e46 Roll src/third_party/skia 7435f2553f53..23775a2e9736 (1 commits) (#6531)
ef0b0f6e9 Roll src/third_party/skia bc7a51e79c5b..7435f2553f53 (1 commits) (#6530)
f46b7b971 Roll src/third_party/skia b28db529c866..bc7a51e79c5b (1 commits) (#6529)
9033c3902 Roll src/third_party/skia 7e67041a1428..b28db529c866 (1 commits) (#6528)
e6887a412 Add missing imports for unicode/utf16.h (#6524)
1242f6dfe Roll src/third_party/skia d38382d060ca..7e67041a1428 (2 commits) (#6527)
a1bbea77c Add a no-op platform view layer. (#6505)
2bb3afad8 Roll src/third_party/skia 21bd60daa3f3..d38382d060ca (10 commits) (#6526)
75e875240 Fix the Mac embedder build (#6525)
436f9707b Add version check for dismissable (#6522)
7767c785b Provide a default GL function resolver in the embedder (#6523)
32841dd89 Case-insensitive matching of family names for custom fonts (#6519)
a9076c7e6 Roll src/third_party/skia 419709dbb167..21bd60daa3f3 (11 commits) (#6520)
f2e7441b5 An API for loading fonts from a buffer provided by the application (#6508)
05aac0f27 fix ResourceExtractor npe. (#6461)
cf5a2a145 Roll src/third_party/skia b27a9cf2f4a8..419709dbb167 (16 commits) (#6517)
84fe4a9f7 Re-revert invalid line height tests (#6516)
5f529566c Add support for text shadows (#6385)
e44c10c96 Reland "Share engine layers with the framework" (#6412) (#6468)
ba0449971 Roll Dart to 1f4dfce179c8f05c9e48759300a15e671b88cc10 (#6515)

TextTheme.apply was incorrectly applying displayColor to the TextTheme's headline, title, subhead, body1, and body2 TextStyle colors. In all cases it should have been bodyColor.

Users can set `PaintingBinding.decodedCacheRatioCap` to control the max
amount of memory used per image to avoid decoding frames each animation
loop.

This depends on flutter/engine#6310.

Fixes #20998, and fixes #14344

Service extensions can only be activated in debug or profile mode, their code should never be included in release mode. This PR adds guards around all service extension registration calls that enable Dart's tree shaker to remove the extension's code in release mode, which reduces our binary size:

Android Snapshot (uncompressed): minus 127,384 Bytes (-124.40KB)
APK (compressed): minus 38,136 Bytes (-37.24KB)
iOS Snapshot (App.framework, uncompressed): 264,304 Bytes(-258.10KB)

For details: https://docs.google.com/document/d/13JlgvliCn5sWwT2K2SfDwD1NhEfxpJH9DCf22gZZru8/edit

**Benchmark Regressions:** This PR may cause benchmarks to regress because it may change the timing of GC. If you notice a benchmark regression **please note down the exact set of benchmarks that regressed on this PR** and then feel free to revert. I will follow-up with a PR that forces a GC before the effected benchmarks run to get a clean baseline before re-applying this PR.

This reverts commit 80f80ab0.

Goldens updated due to Skia AA changes. We previously also made a mistake by having a golden test run on MacOS.

git log 3ffa36295234..50c2e69da --no-merges --oneline
50c2e69da Roll src/third_party/skia 1b62fad4b188..b27a9cf2f4a8 (1 commits) (flutter/engine#6514)
8757bf2a1 Roll src/third_party/skia 05caa69a3f5a..1b62fad4b188 (2 commits) (flutter/engine#6513)
c2fd10ad1 Roll src/third_party/skia 2a138544646d..05caa69a3f5a (1 commits) (flutter/engine#6512)

https://github.com/flutter/engine/compare/35ba11eb49e8...3ffa36295234

git log 35ba11eb49e8..3ffa36295234 --no-merges --oneline
3ffa36295 Add a callback for iOS when the first Flutter frame is rendered (flutter/engine#6135)


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https://github.com/flutter/engine/compare/daf4447a2eb2...35ba11eb49e8

git log daf4447a2eb2..35ba11eb49e8 --no-merges --oneline
35ba11eb4 Roll src/third_party/skia e7588323d586..2a138544646d (2 commits) (flutter/engine#6510)
f95bad849 Roll src/third_party/skia a631669e50a2..e7588323d586 (8 commits) (flutter/engine#6509)


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

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For G3 Roll:

* Revert "MaterialButton must honor its minWidth and height parameters (#22919)"

This reverts commit a0233233.

* Revert "Update uses of ButtonTheme.bar: pass along the current Theme's colorScheme (#22827)"

This reverts commit 655bf6a2.

* Revert "ButtonTheme.of().colorScheme defers to Theme (#22880)"

This reverts commit a590940e.

* Revert "Bring TextTheme into alignment with the current Material spec (#22330)"

This reverts commit 8bfb4b3e.

* Revert "Added ColorScheme, updated ThemeData, ButtonTheme, material buttons (#22013)"

This reverts commit eea3465a.

* Manual adjustments to fix reversion issues.

https://github.com/flutter/engine/compare/9cad7b663ee2...daf4447a2eb2

git log 9cad7b663ee2..daf4447a2eb2 --no-merges --oneline
daf4447a2 Reland "Allow raster caching any layer subtree (#6442)" (flutter/engine#6507)
c6e6da512 Revert "Allow raster caching any layer subtree (#6442)" (flutter/engine#6506)
6447418f7 Allow raster caching any layer subtree (flutter/engine#6442)


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

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* added test

https://github.com/flutter/engine/compare/22522c0b3e69...9cad7b663ee2

git log 22522c0b3e69..9cad7b663ee2 --no-merges --oneline
9cad7b663 Roll src/third_party/skia 9c37cd96e4c8..a631669e50a2 (12 commits) (flutter/engine#6501)
ee53ae1ea Roll src/third_party/skia 932759e9b414..9c37cd96e4c8 (1 commits) (flutter/engine#6498)


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* prefer_void_to_null in flutter_test

* fix CI