     next = next.shadowRoot.elementFromPoint(x, y);
        // on Safari, elementFromPoint may return the shadowRoot host
        if (oldNext === next) {
          break;
        }
        if (next) {
          node = next;
        }
      }
      return node;
    },
    /**
     * a cheaper check than ev.composedPath()[0];
     *
     * @private
     * @param {Event} ev Event.
     * @return {HTMLElement} Returns the event target.
     */
    _findOriginalTarget: function(ev) {
      // shadowdom
      if 