Roll third_party/polymer.

third_party/polymer/v1_0/components-chromium/paper-dropdown-menu/paper-dropdown-menu-extracted.js

 (function() {
       'use strict';
 
       Polymer({
         is: 'paper-dropdown-menu',
 
-        /**
-         * Fired when the dropdown opens.
-         *
-         * @event paper-dropdown-open
-         */
-
-        /**
-         * Fired when the dropdown closes.
-         *
-         * @event paper-dropdown-close
-         */
-
         behaviors: [
           Polymer.IronButtonState,
           Polymer.IronControlState,
           Polymer.IronFormElementBehavior,
           Polymer.IronValidatableBehavior
         ],
 
         properties: {
           /**
            * The derived "label" of the currently selected item. This value
@@ skipping 234 matching lines @@
 
         _openedChanged: function() {
           var openState = this.opened ? 'true' : 'false';
           var e = this.contentElement;
           if (e) {
             e.setAttribute('aria-expanded', openState);
           }
         }
       });
     })();