anchor.diff:      String lastTimestamp = device.lastLogcatTimestamp;
       if (lastTimestamp != null)
         args.addAll(<String>['-T', lastTimestamp]);
  -    args.addAll(<String>[
  -      '-s', 'flutter:V', 'FlutterMain:V', 'FlutterView:V', 'AndroidRuntime:W', 'ActivityManager:W', 'System.err:W', '*:F'
  -    ]);
       runCommand(device.adbCommandForDevice(args)).then((Process process) {
         _process = process;
         _process.stdout.transform(UTF8.decoder).transform(const LineSplitter()).listen(_onLine);
  
positive.code:     });
    }
  
    void _onLine(String line) {
      // Filter out some noisy ActivityManager notifications.
      if (line.startsWith('W/ActivityManager: getRunningAppProcesses'))
        return;
      _linesController.add(line);
    }
  
    void _stop() {
  
negative.code: 
    final AndroidDevice device;
  
    bool _lastWasFiltered = false;
  
    StreamController<String> _linesController;
    Process _process;
  
  