MD Settings: fix double-tap to hide advanced bug

chrome/browser/resources/settings/settings_menu/settings_menu.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview
  * 'settings-menu' shows a menu with a hardcoded set of pages and subpages.
  */
 Polymer({
   is: 'settings-menu',
@@ skipping 11 matching lines @@
 
     /**
      * Dictionary defining page visibility.
      * @type {!GuestModePageVisibility}
      */
     pageVisibility: {
       type: Object,
     },
   },
 
+  ready: function() {
+    // When a <paper-submenu> is created with the [opened] attribute as true,
+    // its _active member isn't correctly initialized. See this bug for more
+    // info: https://github.com/PolymerElements/paper-menu/issues/88. This means
+    // the first tap to close an opened Advanced section does nothing (because
+    // it calls .open() on an opened menu instead of .close(). This is a fix for
+    // that bug without changing that code through its public API.
+    //
+    // TODO(dbeam): we're currently deciding whether <paper-{,sub}menu> are
+    // right for our needs (there have been minor a11y problems). If we decide
+    // to keep <paper-{,sub}menu>, fix this bug with a local Chrome CL (ex:
+    // https://codereview.chromium.org/2412343004) or a Polymer PR (ex:
+    // https://github.com/PolymerElements/paper-menu/pull/107).
+    if (this.advancedOpened)
+      this.$.advancedPage.open();
+  },
+
   /**
    * @param {!settings.Route} newRoute
    */
   currentRouteChanged: function(newRoute) {
     // Make the three menus mutually exclusive.
     if (settings.Route.ABOUT.contains(newRoute)) {
       this.aboutSelected_ = true;
       this.$.advancedMenu.selected = null;
       this.$.basicMenu.selected = null;
     } else if (settings.Route.ADVANCED.contains(newRoute)) {
@@ skipping 21 matching lines @@
 
   /**
    * @param {boolean} opened Whether the menu is expanded.
    * @return {string} Which icon to use.
    * @private
    * */
   arrowState_: function(opened) {
     return opened ? 'settings:arrow-drop-up' : 'cr:arrow-drop-down';
   },
 });