onChangeEnd() {
    // They just let go of the seek bar, so cancel the timer and manually
    // call the event so that we can respond immediately.
    this.seekTimer_.tickNow();
    this.controls.setSeeking(false);

    if (this.wasPlaying_) {
      this.video.play();
    }

    if (this.isMoving_) {
      this.isMoving_ = false;
      this.hideThumbnailTimer_.stop();
      this.hideThumbnailTimer_.tickAfter(/* seconds= */ 0.25);
    }
  }
Called by the base class when user interaction with the input element
ends.

@override