ref(video): use videoTrack from props

It doesn't seem like videoTrack needs to be set onto state
if it can be accessed directly from props. Removing the state
automatically removes the deprecated componentWillReceiveProps.

react/features/base/media/components/AbstractVideoTrack.js

     zoomEnabled?: boolean
 };
 
-/**
- * The type of the React {@code Component} state of {@link AbstractVideoTrack}.
- */
-type State = {
-
-    /**
-     * The Redux representation of the participant's video track.
-     */
-    videoTrack: Object | null
-};
-
 /**
  * Implements a React {@link Component} that renders video element for a
  * specific video track.
  *
  * @abstract
  */
-export default class AbstractVideoTrack<P: Props> extends Component<P, State> {
+export default class AbstractVideoTrack<P: Props> extends Component<P> {
     /**
      * Initializes a new AbstractVideoTrack instance.
      *
     constructor(props: P) {
         super(props);
 
-        this.state = {
-            videoTrack: _falsy2null(props.videoTrack)
-        };
-
         // Bind event handlers so they are only bound once for every instance.
         this._onVideoPlaying = this._onVideoPlaying.bind(this);
     }
 
-    /**
-     * Implements React's {@link Component#componentWillReceiveProps()}.
-     *
-     * @inheritdoc
-     * @param {Object} nextProps - The read-only props which this Component will
-     * receive.
-     * @returns {void}
-     */
-    componentWillReceiveProps(nextProps: P) {
-        const oldValue = this.state.videoTrack;
-        const newValue = _falsy2null(nextProps.videoTrack);
-
-        if (oldValue !== newValue) {
-            this._setVideoTrack(newValue);
-        }
-    }
-
     /**
      * Implements React's {@link Component#render()}.
      *
      * @returns {ReactElement}
      */
     render() {
-        const { videoTrack } = this.state;
+        const videoTrack = _falsy2null(this.props.videoTrack);
         let render;
 
         if (this.props.waitForVideoStarted && videoTrack) {
             this.props.dispatch(trackVideoStarted(videoTrack.jitsiTrack));
         }
     }
-
-    /**
-     * Sets a specific video track to be rendered by this instance.
-     *
-     * @param {Track} videoTrack - The video track to be rendered by this
-     * instance.
-     * @protected
-     * @returns {void}
-     */
-    _setVideoTrack(videoTrack) {
-        this.setState({ videoTrack });
-    }
 }
 
 /**