* Add punctuation for unterminated sentences in doc comments

* Addressing review nit

Fixes https://github.com/flutter/flutter/issues/39526

Needs https://github.com/flutter/engine/pull/20013 to land and roll first.

google3 callsites are updated, remove global lookup from constructor parameters.

Add feature flags for android, ios, and fuchsia (on by default). After updating the g3 rollers, the fuchsia feature will be turned off by default. Creates a simpler base type of feature flags for g3 to extend.

Updates android, ios, fuchsia workflows to use feature flags check.
Removes concept of stable artifacts and checks on flutter version.

Fixes #58999
#52859
#12768

Roll packages, update XML deprecations.

The global packages path could cause tests to fail when it would be overriden to unexpected (in test setup) values. Remove most usage and make it a configuration on buildInfo, along with most other build information. Cleanup the asset builder to require the .packages path and the resident runners to no longer require it, since they already have the information in build_info.

It needs to stick around for the fuchsia deps we do not control.

Filled #60232 for remaining work.

* Word substitutions

* ++

instead of restricting profile/release mode based on whether the tool thinks the device is an emulator, restrict based on the device target architecture and the requested build mode. Notably, this enables release mode on x86_64 Android emulators, but not x86 emulators since we do not support that as an AOT target.

This does not add release mode support for simulators, since this requires us to build and upload artifacts for simulator/x86_64

Also combines experiments into extraGenSnapshot/ExtraFrontEndOptions. Allows providing --no-sound-null-safety to allow out of order migration and running.

This reverts commit 602d8baf.

Ensure iOS and android builds can be correctly cached. Use the performance-measurement-file to verify that all targets were skipped on the second invocation. This is only run on the flutter_gallery build.

Support bundling SkSL shaders into an android APK or appbundle via the --bundle-sksl-path command line options. If provided, these are validated for platform engine revision and then placed in flutter_assets/io.flutter.shaders.json

The resident runner does not check if the ApplicationPackage is null when trying to stop the app. Update AndroidDevice.stopApp to handle this case by returning false.

The package will be null when flutter attach is used.

Prefer using `.of()` (which is statically type-checked) over
`.from()` (which is dynamically type-checked) when possible.

This reverts commit b8bd09db.