anchor.diff:  /// app with Firebase plugins in a scratch pub package.
   ///
   /// See [_pubDependenciesFile] for the location of the dependencies files.
  -void _updateDependenciesFile({
  +Future<void> _updateDependenciesFile({
     required String flutterToolPath,
     required String channel,
   }) async {
  
positive.code: @Depends(sdkInit)
  void updatePubDependencies() async {
    final sdk = _getSdk();
    _updateDependenciesFile(
        flutterToolPath: sdk.flutterToolPath, channel: _channel);
  }
  
  
negative.code:       dependencies: _parsePubDependenciesFile(channel: channel));
    joinFile(dir, ['pubspec.yaml']).writeAsStringSync(pubspec);
  
    await _runFlutterPackagesGet(sdk.flutterToolPath, dir);
  
    // locate the artifacts
    final flutterPackages = ['flutter', 'flutter_test'];
  