anchor.diff:  import 'package:kernel/ast.dart' show Component, Library;
   import 'package:kernel/target/targets.dart';
   import 'package:vm/target/vm.dart';
  +import 'package:vm/target/flutter.dart';
  +import 'package:vm/target/flutter_runner.dart';
   import 'package:compiler/src/kernel/dart2js_target.dart';
   
   main(List<String> args) async {
  
positive.code:       negatable: true,
        help: 'Whether to only build summary files.')
    ..addOption('target',
        allowed: const ['vm', 'dart2js', 'ddc'],
        help: 'Build kernel for the vm, dart2js, or ddc')
    ..addOption('dart-sdk-summary')
    ..addMultiOption('input-summary')
    ..addMultiOption('input-linked')
  
negative.code:       target = new VmTarget(targetFlags);
        if (summaryOnly) {
          out.writeln('error: --summary-only not supported for the vm target');
        }
        break;
      case 'flutter':
        target = new FlutterTarget(targetFlags);
        if (summaryOnly) {
          throw new ArgumentError(
              'error: --summary-only not supported for the flutter target');
        }
        break;
      case 'flutter_runner':
        target = new FlutterRunnerTarget(targetFlags);
        if (summaryOnly) {
          throw new ArgumentError('error: --summary-only not supported for the '
              'flutter_runner target');
        }
        break;
      case 'dart2js':
  