* Starts using the `--source` flag to compile the dart registrant.

* updated general.shard tests

* Fixed the resident compiler flow

* added integration test

* made the integration test self contained

* renamed generated_main to dart_plugin_registrant

* cleaned up for review

* added task runner for ci

* added bringup and TESTOWNERS

* updated failure message

This reverts commit c74a646b.

* e97c8016e Started looking for the dart plugin registrant at runtime  (flutter/engine#31418)

* 9ebbc6eb0 Standardize the embedder file name. (flutter/engine#31723)

* e983ac898 Roll Skia from 1fc0c1c0f8af to 5deac304821b (2 revisions) (flutter/engine#31725)

* afd334d9d added dart plugin registrant test executables to run_tests.py (flutter/engine#31726)

* 0ff508b54 Standardize embedder archive name. (flutter/engine#31693)

* 9c1daae1e Roll Fuchsia Mac SDK from qGsRXn7-D... to RIOZP5nXz... (flutter/engine#31730)

* ceec638bb Roll Fuchsia Linux SDK from _mwyhkd9H... to 7rB0Yrprs... (flutter/engine#31731)

* 54050b405 Roll Skia from 5deac304821b to c3e7a2a00b0a (3 revisions) (flutter/engine#31732)

* a5718ab3c Roll Dart SDK from c3e3126a598b to 34a5563af80d (6 revisions) (flutter/engine#31734)

* migrates lib/foundation and lib/widgets

* migrates lib/painting and lib/material

* migrates lib/cupertino, lib/gestures, lib/services, lib/semantics and lib/rendering

* fixes failing tests

* migrates test/

* improves hashing of lists

Added the navigation_rail.json as well.

See https://github.com/flutter/flutter/issues/99248