Moves the flutter root initialization to a static method on the cache. This is a small step towards making this functionality non-static and instead injected like normal members - however, completely removing all of the static-ness at once was too large of a change.
Instead document and add unit tests and change existing code as little as possible.
#47161
Remove globals from the flutter validator class, and refactor the tests into a separate file. Applies some other cleanup like adding doc comments, and making the doctor validator work like it is documented to work - removing the gen_snapshot check if the artifact is not downloaded instead of downloading all android artifacts.
#47161
Make the logic for locating a local engine path part of its own class, add documentation, and update tests to cover engine source path locating too.
#47161
The flutter tool is currently unable to detect missing permissions in gradle/gradle.bat that would cause a gradle build to fail via process exception. Rather than crashing and exiting, we can display the exception as an error message and tool exit.
While linux/macOS are able to add the +x bit, this is not possible on windows with our current file system/OS API. These crashes represent a substantial amount of crash reporting, but are otherwise not actionable on our end.
The tool was setting the output preferences in a sub-context. Originally these were not injected before the arg parsers were created, though that was fixed by the lazy command creation. Once local engine is removed, the inner flutter_command Zone can be removed.
Make it possible for all FlutterCommands to be global free, by moving instantiation to inside the Zone context. Additionally, provide VerboseLogger and NotifyLogger (daemon) at the top level and remove from command-specific overrides.
This allows removing a work around where web devices needed to look up directly from the context in non-test code.
Technically the output preferences are still zone injected, but these will be moved soon as they were not being used correctly by the top level command (the injection comes after ArgParser reads the overflow values, causing numerous wrap issues)
The `runZoned` method deprecates the `onError` parameter.
Invocations using that parameter must use `runZonedGuarded` instead.
This prepares Flutter for the deprecation. The same places need to be migrated to using
`runZonedGuarded` when the SDK change has been ported to Flutter.
Then the deprecated member will be removed in a follow-up CL when the most important
packages have been migrated.
