* Add a detach command to detach without terminating

Fixes #21154.

* Bump protocol version for app.detach

* Tweak to detach/quit text

* Change logPrefix to named param

Move asset_bundle_package_test to MemoryFileSystem to avoid setting fs.currentDirectory in tests (#21427)

* Update asset_bundle_package_test to use MemoryFileSystem

This updates all tests in this file to use a memory filesystem (same as I did for asset_bundle_package_font_test) based on the current platform.

There were already a few minor tests at the bottom using a MemoryFileSystem and being run for all platforms - however this complicated the shared code I changed above to support Windows natively so I changed them to also work the same as others (that is, they just run the native platforms so require running on all to get full coverage - though this is the case for almost all other tests anyway).

* Move fixPath to the correct place

* Add a failing test for #21418

* Filter workflows to only those applicable to the current platform

Fixes #21418.

* First step in Flutter Doctor refactor. Assigns categories to all validators.

* Revert "Roll engine e54bc4ea1832..a84b210b3d26 (6 commits) (#20453)"

This reverts commit 05c2880a.

* Split iOS and Android workflows into workflow and validator classes.

* Change ValidatorCategory to handle standalone validators that share a
category (e.g. IntelliJ).

Also make Android Studio and Android toolchain use separate categories.

At this stage, flutter doctor output matches what it was previously.
(The summary() method itself has not yet been changed )

* Change doctor summary code to support validator categories.

Output is still unchanged.

* Handle small formatting issues.

* Flip Flutter category's isGroup field to false until it's actually
needed.

* Revert auto-generated formatting changes to keep those lines from
muddying the pull.

* Small fixes pointed out by analyzer.

* Properly fix analyzer issues around const constructors.

* Small changes to address comments.

* Add tests to verify grouped validator behavior and validationtype
merging.

* Update doctor.dart

* Add comments for clarification.

* Added size to stepper icons

* Added Stepper icons size test

Dart 1 is no longer supported in Flutter. Hot reload now always occurs
via kernel file updates (plus any asset bundle changes).

Closes #3188

Dart 1 is no longer supported in Flutter.

This reverts commit 3306fc10.

Enable taking screenshots of arbitrary RenderObjects from a running application from within the inspector.

Key functionality is in the added _ScreenshotPaintingContext class.

Script snapshots were only every used in Dart 1 mode, which is no longer
supported.

Added InheritedModel:  An InheritedWidget that's intended to be used as the base class for models whose dependents may only depend on one part or "aspect" of the overall model.

* Change assert_bundle_package_font_test to memory file system

This is to work towards being able to run the tests without `-j1` (#21113). These tests were using the real filesystem and setting/relying on fs.currentDirectory. There was a comment about this being because the memory provider didnt' support POSIX and Windows, however that seems to have changed since (and many other asset tests already do something similar to this).

* Trim trailing whitespace

* Add a workaround for Windows path slash directions

Strictly this is correct, but the real FS can tolerate either path. The in-memory file system is more strict (see https://github.com/google/file.dart/issues/112).

* Extract a helper for writing schema files in tests

* Missed file when saving!

* Remove redundant comment

* Rename writeBasicSchema -> writeEmptySchema

* Use the file we already have to write contents

* Make comments more descriptive

* Remove another dupe of writeSchema to use the shared one

* Rename schema -> pubspec_schema

* Trim whitespace

This patch eliminates the --preview-dart-2/--no-preview-dart-2 flag,
hardcoding all uses to true. It also defaults all previewDart2 method
parameters to true, where they hadn't yet been.

A series of subsequent patches will eliminate all previewDart2
parameters and the associated code from within the codebase.

* Unskip integration tests on Windows that now pass

The referenced issue is closed and these tests pass for me locally on Windows now.

* Remove import that's no longer used

* Add another issue that is afffecting these tests on Windows

* Add a hot restart test and mark skip on Windows

Skipped due to https://github.com/flutter/flutter/issues/21348.

https://github.com/flutter/engine/compare/77fad1a731f2...de4c7a53f21c

git log 77fad1a731f2..de4c7a53f21c --no-merges --oneline
de4c7a53f Roll src/third_party/skia 09a7bb222172..88119de2b849 (1 commits) (flutter/engine#6146)


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, who should
be CC'd on the roll, and stop the roller if necessary.

https://github.com/flutter/engine/compare/2318a5274af4...77fad1a731f2

git log 2318a5274af4..77fad1a731f2 --no-merges --oneline
77fad1a73 Roll src/third_party/skia 2f53025e8bf1..09a7bb222172 (1 commits) (flutter/engine#6144)


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If the roll is causing failures, please contact the current sheriff, who should
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https://github.com/flutter/engine/compare/d88e0b8229ec...2318a5274af4

git log d88e0b8229ec..2318a5274af4 --no-merges --oneline
2318a5274 Roll src/third_party/skia ca858b68c34b..2f53025e8bf1 (1 commits) (flutter/engine#6143)


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/949fb0fb4cbe...d88e0b8229ec

git log 949fb0fb4cbe..d88e0b8229ec --no-merges --oneline
d88e0b822 Roll src/third_party/skia 2f8c60e28682..ca858b68c34b (2 commits) (flutter/engine#6142)


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https://github.com/flutter/engine/compare/a4471589f2cd...949fb0fb4cbe

git log a4471589f2cd..949fb0fb4cbe --no-merges --oneline
949fb0fb4 Roll src/third_party/skia 8534723c7be1..2f8c60e28682 (1 commits) (flutter/engine#6141)


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, who should
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https://github.com/flutter/engine/compare/017dafd42660...a4471589f2cd

git log 017dafd42660..a4471589f2cd --no-merges --oneline
a4471589f Roll src/third_party/skia e8e12e89c46b..8534723c7be1 (1 commits) (flutter/engine#6140)
db3484f27 Fix crash in text layout when GetMinikinFontCollectionForStyle returns null. (flutter/engine#6139)
0f7bfeaf4 Roll src/third_party/skia 6487e5ca6f10..e8e12e89c46b (1 commits) (flutter/engine#6138)
f25d89a2d Fix windows embedder builds. (flutter/engine#6137)
b3c778fe9 Allow embedders to specify software renderer configs. (flutter/engine#6133)
da419912d Roll src/third_party/skia 7bfe8438a94b..6487e5ca6f10 (6 commits) (flutter/engine#6136)
f44c0008b Roll src/third_party/skia 62db8d577931..7bfe8438a94b (20 commits) (flutter/engine#6134)
fbf672643 Mark deprecated Flutter iOS APIs as unavailable (flutter/engine#6124)


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This was a bug, when e.g a LongPressGestureRecognizer was in the gesture
arena, the android view gesture team may not yet win the arena when the
last pointer was up. This change allows AndroidView to win the gesture
even after all pointers are up.

https://github.com/flutter/engine/compare/f612a761c2f0...017dafd42660

git log f612a761c2f0..017dafd42660 --no-merges --oneline
017dafd42 Roll buildroot to 35959f6255c341eee550884ed69afd6b2891bd53 (unbreaks Windows) (flutter/engine#6132)
842546824 Roll buildroot to pick up new NDK r17b (flutter/engine#6131)


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