anchor.diff:            'locally. Defaults to \$FLUTTER_ENGINE if set, or tries to guess at\n'
             'the location based on the value of the --flutter-root option.',
     )
  +  ..addOption(
  +    'luci-builder',
  +    help: '[Flutter infrastructure] Name of the LUCI builder being run on.'
  +  )
     ..addFlag(
       'match-host-platform',
       defaultsTo: true,
  
positive.code: 
  /// The path to the engine "src/" directory.
  String localEngineSrcPath;
  
  /// Whether to exit on first test failure.
  bool exitOnFirstTestFailure;
  
negative.code: 
      if (serviceAccountTokenFile != null) {
        final Cocoon cocoon = Cocoon(serviceAccountTokenPath: serviceAccountTokenFile);
        /// Cocoon's definition of a task is more specific than [taskName], and to
        /// upload we instead send the [luciBuilder] this is running on.
        await cocoon.sendTaskResult(taskName: luciBuilder, result: result);
      }
  
      if (!result.succeeded) {
  