anchor.diff:    Device _device;
     Device get device => _device;
   
  +  /// Subscription to log messages printed on the device or simulator.
  +  // ignore: cancel_subscriptions
  +  StreamSubscription<String> _deviceLogSubscription;
  +
     int get debugPort => int.parse(argResults['debug-port']);
   
     @override
  
positive.code:   printTrace('Stopping application.');
    ApplicationPackage package = command.applicationPackages.getPackageForPlatform(command.device.platform);
    bool stopped = await command.device.stopApp(package);
    return stopped ? 0 : 1;
  }
  
negative.code:     platformArgs['trace-startup'] = command.traceStartup;
  
    printTrace('Starting application.');
  
    // Forward device log messages to the terminal window running the "drive" command.
    command._deviceLogSubscription = command.device.logReader.logLines.listen(printStatus);
  
    LaunchResult result = await command.device.startApp(
      package,
      command.getBuildMode(),
  