anchor.diff:      if (_fin) {
         switch (_currentMessageType) {
           case _WebSocketMessageType.TEXT:
  -          _eventSink.add(UTF8.decode(_payload.takeBytes()));
  +          _eventSink.add(UTF8.decode(_takePayload()));
             break;
           case _WebSocketMessageType.BINARY:
  -          _eventSink.add(_payload.takeBytes());
  +          _eventSink.add(_takePayload());
             break;
         }
         _currentMessageType = _WebSocketMessageType.NONE;
  
positive.code:       _eventSink.addError(error, stackTrace);
  
    void close() => _eventSink.close();
  
    /**
     * Process data received from the underlying communication channel.
  
negative.code: 
    final bool _serverSide;
    final List _maskingBytes = new List(4);
    final List<Uint8List> _payloads = new List<Uint8List>();
  
    _WebSocketProtocolTransformer([this._serverSide = false]);
  
  