@Override
 public void onError(PublisherKit publisherKit, OpentokError opentokError) {
   Log.v(TAG, "Stream error: " + opentokError.toString());
 }
 @Override
 public void onError(Session session, OpentokError opentokError) {
   Log.v(TAG, "Error in session " + session.getSessionId() + ": " + opentokError.toString());
 }