Update the flutter_gallery Slider demo by aligning the text field in the first slider, adding range slider examples (including custom range thumbs), and separating single slider and range slider examples with tabs.

Fixes a bug in the Range Sider where the onChangeStart and onChangeEnd were not being called if the initial thumb selection came from a drag (rather than a tap).

https://github.com/flutter/engine/compare/4444c9cb6c9f...297cbd4b153b

git log 4444c9cb6c9f1859c1807cff415cd716bb9612ff..297cbd4b153bde91a821a2a07be36948df10ccbd --no-merges --oneline
297cbd4b1 Convert RRect.scaleRadii to public method (flutter/engine#9452)
14d2954a5 Eliminate unused import in FlutterView (flutter/engine#9439)
ccb5034d5 Generate weak pointers only in the platform thread (flutter/engine#9431)
da29c0473 Roll src/third_party/skia 6ce447a4ec20..91032f8cd7ea (5 commits) (flutter/engine#9455)

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https://github.com/flutter/engine/compare/0f2ab22abb2c...4444c9cb6c9f

git log 0f2ab22abb2c8744be7cd5054f7a7b2af65eacd9..4444c9cb6c9f1859c1807cff415cd716bb9612ff --no-merges --oneline
4444c9cb6 Roll src/third_party/skia 089f13f98286..6ce447a4ec20 (1 commits) (flutter/engine#9453)
552a72932 Roll src/third_party/skia 38daf0be45e4..089f13f98286 (2 commits) (flutter/engine#9451)

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0f2ab22ab Roll src/third_party/skia 8b5cf82dca37..38daf0be45e4 (1 commits) (flutter/engine#9448) (#34961)


https://github.com/flutter/engine/compare/1be3ee342c8f...0f2ab22abb2c

git log 1be3ee342c8f57d223b21e346803977a980e3ee3..0f2ab22abb2c8744be7cd5054f7a7b2af65eacd9 --no-merges --oneline
0f2ab22ab Roll src/third_party/skia 8b5cf82dca37..38daf0be45e4 (1 commits) (flutter/engine#9448)

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https://github.com/flutter/engine/compare/a41243dcac62...1be3ee342c8f

git log a41243dcac62aa580a5dacd07a9e919b49b14de3..1be3ee342c8f57d223b21e346803977a980e3ee3 --no-merges --oneline
1be3ee342 Revert "Roll fuchsia/sdk/core/mac-amd64 from Cx51FRV5TCoqQ9nfs4E2QMfYkJ1JWt7arQXhV01tr7cC to w-3t4XiGPWI6UnY7zV2vTMAbS83-U8is0P168iq230oC (#9447)" (flutter/engine#9450)
c29d3bae4 Revert "Roll fuchsia/sdk/core/linux-amd64 from udf6w2VmM5E8PyQm5ggugW_jjiEdWs-Xl6efeLf2JdkC to jQ8awqEtcZVdusV29crejq9iQikDKImqn-HGtb4h3dwC (#9443)" (flutter/engine#9449)

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Android now exclusively uses ELF shared libraries, and
iOS uses assembly.

https://github.com/flutter/engine/compare/5429f40bf8c1...a41243dcac62

git log 5429f40bf8c1fed4d6bdcb981b94eac02903b9d5..a41243dcac62aa580a5dacd07a9e919b49b14de3 --no-merges --oneline
a41243dca Roll fuchsia/sdk/core/linux-amd64 from udf6w2VmM5E8PyQm5ggugW_jjiEdWs-Xl6efeLf2JdkC to jQ8awqEtcZVdusV29crejq9iQikDKImqn-HGtb4h3dwC (flutter/engine#9443)
2a83c925f Roll fuchsia/sdk/core/mac-amd64 from Cx51FRV5TCoqQ9nfs4E2QMfYkJ1JWt7arQXhV01tr7cC to w-3t4XiGPWI6UnY7zV2vTMAbS83-U8is0P168iq230oC (flutter/engine#9447)
044b2c2a7 Roll src/third_party/skia 641d2b6e62d9..8b5cf82dca37 (1 commits) (flutter/engine#9444)

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https://github.com/flutter/engine/compare/4b391cbe7e0a...5429f40bf8c1

git log 4b391cbe7e0a4c02fb46e7131749c9c5714bfbc4..5429f40bf8c1fed4d6bdcb981b94eac02903b9d5 --no-merges --oneline
5429f40bf Revert "Roll fuchsia/sdk/core/mac-amd64 from Cx51FRV5TCoqQ9nfs4E2QMfYkJ1JWt7arQXhV01tr7cC to e8sS_5Rpuo7cSjSWPCdxwTEAg2VbS9NPH2tjhBhPwsUC (#9442)" (flutter/engine#9446)
38078dfcd Roll fuchsia/sdk/core/mac-amd64 from Cx51FRV5TCoqQ9nfs4E2QMfYkJ1JWt7arQXhV01tr7cC to e8sS_5Rpuo7cSjSWPCdxwTEAg2VbS9NPH2tjhBhPwsUC (flutter/engine#9442)

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https://github.com/flutter/engine/compare/c46d8c0a155a...4b391cbe7e0a

git log c46d8c0a155a433344dc4e0b65b7a6a23b3ea81b..4b391cbe7e0a4c02fb46e7131749c9c5714bfbc4 --no-merges --oneline
4b391cbe7 Roll src/third_party/skia 31d587474367..641d2b6e62d9 (1 commits) (flutter/engine#9441)
a98612600 Roll src/third_party/skia 6bbeb4ab7222..31d587474367 (1 commits) (flutter/engine#9440)

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https://github.com/flutter/engine/compare/5153075e5fdf...c46d8c0a155a

git log 5153075e5fdfdbcdb2c7e9fae3743ca015c68773..c46d8c0a155a433344dc4e0b65b7a6a23b3ea81b --no-merges --oneline
c46d8c0a1 Update README.md for consistency with framework (flutter/engine#9428)

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5153075e5 Roll src/third_party/skia f3881b278e69..6bbeb4ab7222 (1 commits) (flutter/engine#9438) (#34903)


https://github.com/flutter/engine/compare/d004bcd4d619...5153075e5fdf

git log d004bcd4d619fc3574761d63d7cf7b7291332c79..5153075e5fdfdbcdb2c7e9fae3743ca015c68773 --no-merges --oneline
5153075e5 Roll src/third_party/skia f3881b278e69..6bbeb4ab7222 (1 commits) (flutter/engine#9438)

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https://github.com/flutter/engine/compare/fa16babc4537...d004bcd4d619

git log fa16babc4537967c065605e4e184b206869da1f6..d004bcd4d619fc3574761d63d7cf7b7291332c79 --no-merges --oneline
d004bcd4d Revert "Reland Update harfbuzz to 2.5.2 (#9406)" (flutter/engine#9437)
264d6d578 Reland Update harfbuzz to 2.5.2 (flutter/engine#9406)
f6389583f Ios unit tests choose engine (flutter/engine#9432)
8f20c1bd5 Roll src/third_party/skia 893403fb3896..f3881b278e69 (9 commits) (flutter/engine#9434)
6d2d9c88f Resolves embedding log chattyness by gating verbose, debug, and info logs by level (#34876). (flutter/engine#9425)

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https://github.com/flutter/engine/compare/e32307e9f140...fa16babc4537

git log e32307e9f1409c9f0518956d9c695c1105565201..fa16babc4537967c065605e4e184b206869da1f6 --no-merges --oneline
fa16babc4 Use goma-aware Fuchsia clang toolchain (flutter/engine#9430)

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https://github.com/flutter/engine/compare/a9a0b89b1c82...e32307e9f140

git log a9a0b89b1c82aa657708eece3e690bf39cf0ead5..e32307e9f1409c9f0518956d9c695c1105565201 --no-merges --oneline
e32307e9f Revert "Update harfbuzz to 2.5.2 (#9406)" (flutter/engine#9429)
780343a22 Update harfbuzz to 2.5.2 (flutter/engine#9406)
3757f1992 delegate checkInputConnectionProxy to the relevant platform view (flutter/engine#9426)
d9dfad3b8 Roll src/third_party/skia 8676929c0a13..893403fb3896 (6 commits) (flutter/engine#9421)
91e31dca5 Made the license check ignore the .vscode directory. (flutter/engine#9398)
24c3f513f Roll src/third_party/skia a1d26a807798..8676929c0a13 (9 commits) (flutter/engine#9416)
e33f83edb Roll src/third_party/skia e3beb99f39f0..a1d26a807798 (1 commits) (flutter/engine#9411)

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* Prepare for HttpClientResponse Uint8List SDK change

An upcoming change in the Dart SDK will change `HttpClientResponse`
from implementing `Stream<List<int>>` to instead implement
`Stream<Uint8List>`.

This forwards-compatible change to `_MockHttpClientResponse` is being
made to allow for a smooth rollout of that SDK breaking change. The
current structure of the class is as follows:

```dart
_MockHttpClientResponse extends Stream<List<int>> implements HttpClientResponse {
  ...
}
```

This structure would require that the Dart SDK change land atomically
a change to the class (`extends Stream<Uint8List>`). This atomic landing
requirement doesn't play well at all with Flutter's roll model vis-a-vis
the Dart SDK's roll model to Google's internal repo.  As such, this commit
changes the structure of `_MockHttpClientResponse` to be:

```dart
_MockHttpClientResponse implements HttpClientResponse {
  final Stream<Uint8List> _delegate;

  ...
}
```

Once the Dart SDK change has fully rolled out, we can simplify this class
back to its former structure.

https://github.com/dart-lang/sdk/issues/36900

* Review comment

Change the way outlined inputs vertically align their text to be more similar to how it used to be before a refactor. Fixes an edge case uncovered by a SCUBA test.

a9a0b89b1 Roll src/third_party/skia 5549cb00a2cf..e3beb99f39f0 (4 commits) (flutter/engine#9410) (#34845)


https://github.com/flutter/engine/compare/9c5d08fc7746...a9a0b89b1c82

git log 9c5d08fc7746e7f263439719230c24bdcfffb11e..a9a0b89b1c82aa657708eece3e690bf39cf0ead5 --no-merges --oneline
a9a0b89b1 Roll src/third_party/skia 5549cb00a2cf..e3beb99f39f0 (4 commits) (flutter/engine#9410)

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9c5d08fc7 Roll src/third_party/skia 0c64a545176a..5549cb00a2cf (1 commits) (flutter/engine#9408) (#34832)


https://github.com/flutter/engine/compare/950d4813b5c6...9c5d08fc7746

git log 950d4813b5c6806a01f0225da814f5cb300dd65b..9c5d08fc7746e7f263439719230c24bdcfffb11e --no-merges --oneline
9c5d08fc7 Roll src/third_party/skia 0c64a545176a..5549cb00a2cf (1 commits) (flutter/engine#9408)

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https://github.com/flutter/engine/compare/cd973f8aaeae...950d4813b5c6

git log cd973f8aaeae624feab3288b1d85a1770115909b..950d4813b5c6806a01f0225da814f5cb300dd65b --no-merges --oneline
950d4813b Clamp when overflowing z bounds (flutter/engine#9402)

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https://github.com/flutter/engine/compare/0c874c62d0ad...cd973f8aaeae

git log 0c874c62d0ad596484a83afaa5a6c546d96679fc..cd973f8aaeae624feab3288b1d85a1770115909b --no-merges --oneline
cd973f8aa Added unit tests for the ios code. (flutter/engine#9388)
a2db2ea6f Android Embedding Refactor PR35: Ensure all JNI methods are in FlutterJNI (#34751). (flutter/engine#9391)

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https://github.com/flutter/engine/compare/3b52992902ee...0c874c62d0ad

git log 3b52992902eee1a4e629b693fc82ccb357e5fa44..0c874c62d0ad596484a83afaa5a6c546d96679fc --no-merges --oneline
0c874c62d Avoid a full screen overlay within virtual displays (flutter/engine#9343)
605c63be9 Roll src/third_party/skia 384981be3dd2..0c64a545176a (11 commits) (flutter/engine#9404)
7a5ec8d79 Remove build flags for dynamic patching (flutter/engine#9394)

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https://github.com/flutter/engine/compare/14c3c79f573d...3b52992902ee

git log 14c3c79f573dc35fb9e497ab5cedc5e12716d9e9..3b52992902eee1a4e629b693fc82ccb357e5fa44 --no-merges --oneline
3b5299290 Roll src/third_party/skia 4918bbcbfd54..384981be3dd2 (13 commits) (flutter/engine#9395)
7fc828d1a Workaround fix the platform view dismiss crash related to gl (flutter/engine#9377)

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https://github.com/flutter/engine/compare/a82751503fa6...14c3c79f573d

git log a82751503fa6f910042bc04020bd43756a96903d..14c3c79f573dc35fb9e497ab5cedc5e12716d9e9 --no-merges --oneline
14c3c79f5 libtxt: remove obsolete font_manager_available defines (flutter/engine#9376)
e6d355221 [glfw] Implement SystemNavigator.pop (flutter/engine#9365)
9b130a4bf Roll src/third_party/skia b520476ee6dc..4918bbcbfd54 (4 commits) (flutter/engine#9393)

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* Added some Widgets of the Week to documentation: AspectRatio and AnimatedIcon.

Breaking change to extremely rarely used ParentDataWidget.debugDescribeInvalidAncestorChain api changing the return type of the method from String to DiagnosticsNode.