on-select"`.
         */
        _onIronSelect: function(event) {
          if (!this.ignoreSelect) {
            this.close();
          }
        },

        /**
         * Closes the dropdown when an `iron-activate` event is received if
         * `closeOnActivate` is true.
         *
         * @param {CustomEvent} event A CustomEvent of type 'iron-activate'.
         */
        _onIronActivate: function(event) {
          if (this.closeOnActivate) {
            this.close();
          }
        },

   