anchor.diff:      bool renderVideo =
           (widget._renderer._textureId != null && widget._renderer._srcObject != null);
   
  -    return new LayoutBuilder(
  +    return LayoutBuilder(
           builder: (BuildContext context, BoxConstraints constraints) {
  -      return new Center(
  -          child: renderVideo ? _buildVideoView(constraints) : new Container());
  +      return Center(
  +          child: renderVideo ? _buildVideoView(constraints) : Container());
       });
     }
   }
  
positive.code:         height: constraints.maxHeight,
          child: FittedBox(
              fit: widget.objectFit == RTCVideoViewObjectFit.RTCVideoViewObjectFitContain ? BoxFit.contain : BoxFit.cover,
              child: new Center(
                  child: new SizedBox(
                      width: constraints.maxHeight * _aspectRatio,
                      height: constraints.maxHeight,
                      child: new Transform(
                          transform: Matrix4.identity()
                            ..rotateY(widget.mirror ? -pi : 0.0),
                          alignment: FractionalOffset.center,
                          child:
                              new Texture(textureId: widget._renderer._textureId))))));
    }
  
    @override
  
negative.code:   }
  
    EventChannel _eventChannelFor(int textureId) {
      return EventChannel('FlutterWebRTC/Texture$textureId');
    }
  
    void eventListener(dynamic event) {
  