anchor.diff:          listenerFile.path,
           packages: PackageMap.globalPackagesPath,
           enableObservatory: collector != null,
  +        observatoryPort: explicitObservatoryPort,
  +        diagnosticPort: explicitDiagnosticPort,
         );
         subprocessActive = true;
         finalizers.add(() async {
  
positive.code: typedef Future<Null> _Finalizer();
  
  class FlutterPlatform extends PlatformPlugin {
    FlutterPlatform({ this.shellPath, this.collector }) {
      assert(shellPath != null);
    }
  
    final String shellPath;
    final CoverageCollector collector;
  
    // Each time loadChannel() is called, we spin up a local WebSocket server,
    // then spin up the engine in a subprocess. We pass the engine a Dart file
  
negative.code:       int processObservatoryPort;
        _pipeStandardStreamsToConsole(
          process,
          storeObservatoryPort: (int detectedPort) {
            assert(processObservatoryPort == null);
            assert(explicitObservatoryPort == null || explicitObservatoryPort == detectedPort);
            printTrace('test $ourTestCount: using observatory port $detectedPort from pid ${process.pid} to collect coverage');
            processObservatoryPort = detectedPort;
          },
          startTimeoutTimer: () {
            new Future<_InitialResult>.delayed(_kTestStartupTimeout, () => timeout.complete());
  