/**
  * Handle message sent by {@link #notifyScreenOffLocked()}
  *
  * @see #NOTIFY_SCREEN_OFF
  */
 private void handleNotifyScreenOff() {
   synchronized (KeyguardViewMediator.this) {
     if (DEBUG) Log.d(TAG, "handleNotifyScreenOff");
     mKeyguardViewManager.onScreenTurnedOff();
   }
 }