title: ExoPlayer issue exiting split screen / multi window while playing DRM
body: <p>I have an application that plays DRM-Dash content using ExoPlayer, when the app goes into split screen the playback continues as expected, but exiting split screen makes the FrameView containing ExoPlayer float over the application.</p>
  <p>This issue does not happen when a DRM free stream is played so seems related to the DRM keys</p>
  <p>I'm taking advantage of <code>onMultiWindowModeChanged</code> to try to make ExoPlayer stick to it's original surface but I ran out of options.</p>
  <p>Tried detaching the view and re-attaching but the issue persists</p>
  <pre class="lang-java prettyprint-override"><code>public void requestRebuild() {
    detachViewFromParent(exoPlayerView);
    LayoutParams layoutParams = getDefaultLayoutParams();
    exoPlayerView.setLayoutParams(layoutParams);
    attachViewToParent(exoPlayerView, 0 , layoutParams);
    exoPlayerView.setPlayer(player);
    startPlayback();
  }
  </code></pre>
  <p>Also recreating the View but playback breaks</p>
  <pre class="lang-java prettyprint-override"><code>public void requestRebuild() {
    removeView(exoPlayerView);
    exoPlayerView = new ExoPlayerView(getContext());
    LayoutParams layoutParams = getDefaultLayoutParams();
    exoPlayerView.setLayoutParams(layoutParams);
    addView(exoPlayerView, 0 , layoutParams);
    recreateSimpleExoPlayer();
    selectTrack();
    setSource();
    setControls();
  }
  </code></pre>
  <p>Does anyone have experience re-attaching or re-creating a living ExoPlayer with DRM keys already loaded ?</p>