This updates FadeInImage to use the new Image.frameBuilder
API (added in #33369), to greatly simplify the implementation
of FadeInImage.

This also removes the FadeInImage.placeholderSemanticLabel property.
This property was added in #28799 for the sake of completeness (the bug
it fixed was the lack of any semantic label support in FadeInImage), but a
placeholder is a transient visual artifact, not something that affects the
underlying semantic meaning of the image.

This PR changes ModalRoute so that, when the route on top of it is popped, it requests to focus on the last focus.

Enables the CocoaPods-based plugin workflow for macOS. This allows a
macOS project to automatically fetch and add native plugin
implementations via CocoaPods for anything in pubspec.yaml, as is done
on iOS.

This reverts commit 445505d6.

Fixes https://github.com/flutter/flutter/issues/32750

https://github.com/flutter/engine/compare/f867609c01a9...a32df2c92800

git log f867609c01a90a886d7510fc71bcf3e0597a5f27..a32df2c9280033c93a7ed089c294566dabfbf693 --no-merges --oneline
a32df2c92 Roll src/third_party/skia da95a75be1dd..c4fec06e5a3b (1 commits) (flutter/engine#9154)
79c6ce19a Preserve safe area (flutter/engine#8848)
cbef680a3 Roll src/third_party/skia b9658153032a..da95a75be1dd (2 commits) (flutter/engine#9153)

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* Prep for engine roll

Ran gen_keycodes.dart, which pulled a new keycode from the Chromium source. This PR just checks in that change.

* e8db5dfd5 Always run the resource extractor in FlutterMain (flutter/engine#9149)

* eb566ebb7 Roll src/third_party/skia 65e49ba51b03..89799efe587b (3 commits) (flutter/engine#9150)

* f867609c0 Roll src/third_party/skia 89799efe587b..b9658153032a (2 commits) (flutter/engine#9152)

https://github.com/flutter/engine/compare/e87326dd7d42...7f4f52f95294

git log e87326dd7d42db415b724c4d206703f971160823..7f4f52f95294544a2970e514d163b9791efa9147 --no-merges --oneline
7f4f52f95 Add missing ifndef guard for count_down_latch.h (flutter/engine#9143)
e07fc692b Roll web sdk (flutter/engine#9146)
9ca7edc5b Roll src/third_party/skia f62e575bab08..65e49ba51b03 (10 commits) (flutter/engine#9147)

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

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Use Dart's new direct ELF generator to package AOT blobs as shared libraries in Android APKs (#33611)

This is a replacement for the old implementation of --build-shared-library
that emits an AOT assembly snapshot and feeds it to the Android NDK toolchain.

https://github.com/flutter/engine/compare/f6061fb79448...e87326dd7d42

git log f6061fb794486f9d80f6b5281304783b4b45f5e5..e87326dd7d42db415b724c4d206703f971160823 --no-merges --oneline
e87326dd7 Suppress an unchecked cast warning in ShimPluginRegistry (flutter/engine#9145)

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https://github.com/flutter/engine/compare/37b31ca70523...f6061fb79448

git log 37b31ca70523d0af8b2a9823600688d70220881b..f6061fb794486f9d80f6b5281304783b4b45f5e5 --no-merges --oneline
f6061fb79 Roll src/third_party/dart 39ec9fc4f3..445a23a9bc (4 commits)

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Rather than macos/Flutter containing a mixture of files that should and
shouldn't be checked in, create clear locations for:
- Files that are "owned" by Flutter, but should be checked in
  (Flutter/). This will contain files like the top-level Flutter
  xcconfigs, generated plugin registrants, etc.
- Files that are generated by Flutter on the fly, and should not be
  checked in (Flutter/ephemeral/). This will contain Flutter SDK caches,
  the generated xcconfig, etc.

Also adds Flutter-owned Debug and Release xcconfig variants, in
preparation for PodSpec tooling.

* 49b6de8c5 Dynamically add certain iOS AppDelegate methods. (flutter/engine#8843)

* 75da3d42d Roll src/third_party/dart fee615c5a5..39ec9fc4f3 (46 commits)

* ba6cc8c93 Fix type mismatches in C++ standard codec (flutter/engine#9112)

* 37b31ca70 Roll src/third_party/skia 69aaee0ff927..f62e575bab08 (11 commits) (flutter/engine#9142)

The props file used in the Windows build didn't include the local engine
build flags when applicable.

The text selection handles now feel a lot more responsive, and their implementation was cleaned up a bit.

Tickers being disabled and re-enabled can cause the
condition of a synchronous notification happening after
image frames have been delivered, which is valid in that
case. As such, this removes the assert.

https://github.com/flutter/flutter/issues/32374

This adds DiagnosticableMixin as a mixin class that provides the implementaion for Diagnosticable, so that we can now add diagnostics to classes which already have a base class.

This PR enables "Select all" on MaterialTextSelection when text is partially selected.

This PR solves two problems: currently, the onExit is called for a mouse pointer the moment the removal message is received, except that by the time it actually calls it, there is no _lastEvent for it in the mouse tracker (it's already been removed), resulting in an event being passed to the onExit that contains nulls for the position. Also, removePointer events don't actually get created with a position, although they easily could be, so that even the the _lastEvent in the mouse tracker were still populated, it would still give a null position and delta.

This PR adds support for the position and delta in a PointerRemovedEvent, and populates them. In addition, when a remove event is received, it doesn't actually remove the pointer until the mouse position check that gets scheduled actually happens.

58eff77ef Roll src/third_party/skia 2f0f5fb37d74..69aaee0ff927 (2 commits) (flutter/engine#9138) (#33574)


https://github.com/flutter/engine/compare/061d615bc715...58eff77ef2f8

git log 061d615bc715fd07d966d158b0b8c7637aff5bd7..58eff77ef2f808306f0f8d4e46d910b6210bae46 --no-merges --oneline
58eff77ef Roll src/third_party/skia 2f0f5fb37d74..69aaee0ff927 (2 commits) (flutter/engine#9138)

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

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061d615bc Roll src/third_party/skia 859f7108a5af..2f0f5fb37d74 (2 commits) (flutter/engine#9137) (#33564)


https://github.com/flutter/engine/compare/22fcb2e8d19e...061d615bc715

git log 22fcb2e8d19eb6d4351ae91a4d63ca30c0a0b072..061d615bc715fd07d966d158b0b8c7637aff5bd7 --no-merges --oneline
061d615bc Roll src/third_party/skia 859f7108a5af..2f0f5fb37d74 (2 commits) (flutter/engine#9137)

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22fcb2e8d Roll buildroot to pick up fixed create_updated_flutter.deps.py (flutter/engine#9129) (#33556)


https://github.com/flutter/engine/compare/7dd62d6b3ca4...22fcb2e8d19e

git log 7dd62d6b3ca4c7d00e4382491b5a692a5a4554b1..22fcb2e8d19eb6d4351ae91a4d63ca30c0a0b072 --no-merges --oneline
22fcb2e8d Roll buildroot to pick up fixed create_updated_flutter.deps.py (flutter/engine#9129)

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https://github.com/flutter/engine/compare/fa9b5bd0e286...7dd62d6b3ca4

git log fa9b5bd0e286e91bb685b22adf346e7e19b944d2..7dd62d6b3ca4c7d00e4382491b5a692a5a4554b1 --no-merges --oneline
7dd62d6b3 Roll src/third_party/skia 1013ecfb3421..859f7108a5af (19 commits) (flutter/engine#9136)
e8aa12048 New Plugin API PR5: Integrates plugin lifecycle control with FlutterFragment. (flutter/engine#9083)
8b1199c4d Implemented Log proxy that only logs in BuildConfig.DEBUG (#25391). (flutter/engine#9122)

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https://github.com/flutter/engine/compare/4c4c0f82825d...fa9b5bd0e286

git log 4c4c0f82825d9aee5aa208da32c9d3cfbd5157e8..fa9b5bd0e286e91bb685b22adf346e7e19b944d2 --no-merges --oneline
fa9b5bd0e Reduce pipeline depth when GPU and Platform are same thread (flutter/engine#9132)
d4794122a Change the virtual display size restriction to warning (flutter/engine#9110)

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https://github.com/flutter/engine/compare/8dc3a4cde207...4c4c0f82825d

git log 8dc3a4cde2075a4f5458fd0eb199627f5124508d..4c4c0f82825d9aee5aa208da32c9d3cfbd5157e8 --no-merges --oneline
4c4c0f828 Add plugin shim to facilitate old plugins in new embedding (#33478). (flutter/engine#9120)
e8c2b1787 Added support for transparent FlutterActivitys (#32740). (flutter/engine#9115)
19c5029b9 Roll src/third_party/skia 29e013deb476..1013ecfb3421 (3 commits) (flutter/engine#9130)
45d39e137 Revert "Roll src/third_party/dart fee615c5a5..d5405d06f4 (21 commits) (#9127)" (flutter/engine#9135)
44f1b440a Revert "Use track-widget-creation transformer included in the sdk. (#9085)" (flutter/engine#9134)
ae14c5a24 Roll src/third_party/dart fee615c5a5..d5405d06f4 (21 commits) (flutter/engine#9127)
3ea7ac8d9 Roll src/third_party/skia 633db4db7672..29e013deb476 (3 commits) (flutter/engine#9128)
8ad0e2f8e Roll src/third_party/skia 25b63f91b3b4..633db4db7672 (4 commits) (flutter/engine#9125)
37e6e0c90 Roll src/third_party/skia 8f88b2da05d5..25b63f91b3b4 (2 commits) (flutter/engine#9121)
37b367e4d Allow specifying both Dart and non-Dart fixtures in engine unit-tests. (flutter/engine#9113)
28f2c05a6 Roll src/third_party/skia 1f02e8488551..8f88b2da05d5 (3 commits) (flutter/engine#9116)
093200848 Remove outdated TODOs (flutter/engine#9114)
c880ca215 Roll src/third_party/dart 50b0d85804..fee615c5a5 (4 commits)
6e5151359 Removing unused imports (flutter/engine#9108)
9ee269721 Roll src/third_party/skia d04aaa3a841a..1f02e8488551 (8 commits) (flutter/engine#9109)
fa2e2d9fc Add checks to constructors and add missing constructor members (flutter/engine#9106)
7e1788acd Fix unopt variants of profile and release builds. (flutter/engine#9107)
867120c0c Better help message. (flutter/engine#9097)
e27c6e890 Forward custom IDE flags to GN. (flutter/engine#9023)
6b4ca8da5 Roll src/third_party/skia 176b214f91bc..d04aaa3a841a (7 commits) (flutter/engine#9105)
a20731870 Roll src/third_party/dart ec4d48e241..50b0d85804 (87 commits)
0a6aeb347 Roll src/third_party/skia 213aa46af167..176b214f91bc (2 commits) (flutter/engine#9100)
f2e22aa3c Roll src/third_party/skia 7730d7cb8fb2..213aa46af167 (3 commits) (flutter/engine#9098)
557db42ad Roll src/third_party/skia de7e074e8190..7730d7cb8fb2 (2 commits) (flutter/engine#9096)
64a4a0eaa Roll src/third_party/skia f06b6d5469a5..de7e074e8190 (1 commits) (flutter/engine#9094)
fdee6256a Roll src/third_party/skia 7e5a64f517e4..f06b6d5469a5 (2 commits) (flutter/engine#9093)
daf47f0b4 Roll src/third_party/skia dc01a84ae098..7e5a64f517e4 (1 commits) (flutter/engine#9092)
41e10f07f Fix internal break since listing contents can return null (flutter/engine#9078)
cf1b20318 Roll src/third_party/skia f33c95cd6f55..dc01a84ae098 (3 commits) (flutter/engine#9091)
2404cdc90 Rename macOS FLEPlugin* to FlutterPlugin* (flutter/engine#9074)
509a43fe2 Apply minor cleanups to Android embedding (flutter/engine#9088)
0a0f3305b Removed outdated deprecation comments (flutter/engine#9087)
a44cbbf49 Delete BSDiff sources (flutter/engine#9086)
0f1ff3bdb Correct typos, adopt US spellings (flutter/engine#9081)
651c90409 Use track-widget-creation transformer included in the sdk. (flutter/engine#9085)
cfa524fcd New Plugin API PR4: Adds Lifecycle support to the new plugin system. (flutter/engine#9049)
6b8ac18b8 Roll src/third_party/skia d9430297e74a..f33c95cd6f55 (5 commits) (flutter/engine#9082)
11408effd Update macOS podspec version requirement (flutter/engine#9077)
66c6ae48e Roll src/third_party/skia a4b837971c4b..d9430297e74a (30 commits) (flutter/engine#9080)
9151b377e Roll src/third_party/skia 9339a8a61af0..a4b837971c4b (34 commits) (flutter/engine#9076)
ee6a9c404 Fix unchecked operation warnings in FlutterMain (flutter/engine#9073)
333042cf3 Roll third_party/dart/tools/sdks to 2.3.0 (flutter/engine#9072)
01b8c078c Roll src/third_party/skia f77dbd04b926..9339a8a61af0 (12 commits) (flutter/engine#9065)
26b4fb57f Roll src/third_party/dart e3edfd36b2..ec4d48e241 (7 commits)
9d2d58a3c Add mouse button support to the macOS shell (flutter/engine#9054)
...