anchor.diff:  import 'package:vm/target/flutter_runner.dart';
   import 'package:compiler/src/kernel/dart2js_target.dart';
   
  -main(List<String> args) async {
  +/// [sendPort] may be passed in when started in an isolate. If provided, it is
  +/// used for bazel worker communication instead of stdin/stdout.
  +main(List<String> args, SendPort sendPort) async {
     args = preprocessArgs(args);
   
     if (args.contains('--persistent_worker')) {
  
positive.code: 
  import 'dart:async';
  import 'dart:io';
  
  import 'package:args/args.dart';
  import 'package:bazel_worker/bazel_worker.dart';
  
negative.code:       throw new StateError(
            "unexpected args, expected only --persistent-worker but got: $args");
      }
      await new KernelWorker(sendPort: sendPort).run();
    } else {
      var result = await computeKernel(args);
      if (!result.succeeded) {
  