Work towards https://github.com/flutter/flutter/issues/144835.
Doc (_sorry, internal only_): [go/flutter-engine-goldens-workflow](http://goto.google.com/flutter-engine-goldens-workflow).
This implements the majority of the proposed workflow, that is, optionally having a plain-text version at the root of the directory, and using it to apply a unique suffix we can review in release branches. As it stands, this is a NO-OP outside of tests (it will have no impact, and can be ignored).
What's missing before using this feature in release branches:
- Optimization work with the infra team (not sure if blocking or not):
https://github.com/flutter/flutter/issues/145842
- A dry-run of this with the release team to make sure it works as intended
@gaaclarke As implemented, I _think_ we don't need anything special for [`dir_contents_diff`](286169bb52/tools/dir_contents_diff), but maybe I'm wrong - I think only the _test_ names are being changed, not the names on disk.
/cc @zanderso as well.
Allow users to update dependencies. Examples:
* `et fetch` Fetch dependencies
In the future, `et build` will update dependencies if it detects that they have changed.
Also:
* Updates the status in the README
* Adds instructions on how to run tests
* Fixes `et run`'s description
* Makes the `--verbose` flag global
The `run` command builds both the host and target engines and then invokes `flutter run` so that it runs the app using the custom engine builds.
It is expected that 'et run' be used inside the directory of a flutter application.
Command line flags passed after `--` will be forwarded to `flutter run`.
Some examples:
- `et run` Build the debug variant and runs the app in that mode.
- `et run -- --profile` Build the profile variant and runs the app in that mode.
- `et run -- --release` Build the release variant and runs the app in that mode.
Also:
- Start a local_engine.json builder definition (it is missing a lot)
- Tweak the test fixture.
- Add a new Matcher to litetest.
- Tweaked the build config linter to only care about duplicate build names within the same builder.
Fixes https://github.com/flutter/flutter/issues/140481
Before this fix, if all tests are skipped, the `onDone` callback never fires, which means the recieve port never closes, which means the process just hangs indefinitely (and the success message is never printed).
* Add pkg:smith as a dependency for flutter_frontend_server.
This is needed to roll dart past b453c6bcba
* Update few more packages that depend on internal dart sdk expect package
