us();

        this._renderClosed();
      }
    },

    /**
     * Executes a callback on the next animation frame, overriding any previous
     * callback awaiting for the next animation frame. e.g.
     * `__onNextAnimationFrame(callback1) && __onNextAnimationFrame(callback2)`;
     * `callback1` will never be invoked.
     * @param {!Function} callback Its `this` parameter is the overlay itself.
     * @private
     */
    __onNextAnimationFrame: function(callback) {
      if (this.__raf) {
        wind