[MD settings] remove unneeded properties

chrome/browser/resources/settings/settings_menu/settings_menu.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/av-icons.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/device-icons.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/hardware-icons.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/image-icons.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/iron-icons.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/social-icons.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-menu/paper-menu.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-menu/paper-submenu.html">
@@ skipping 49 matching lines @@
       paper-submenu div {
         @apply(--layout-center);
         -webkit-margin-start: 24px;
         display: flex;
         font-size: 13px;
         font-weight: 500;
         min-height: 40px;
       }
     </style>
     <paper-menu name="root-menu">
-      <paper-submenu opened="{{basicOpened_}}">
-        <div class="menu-trigger" data-page="basic" data-section=""
-            on-tap="openPage_">
+      <paper-submenu data-page="basic" id="basicPage">
+        <div class="menu-trigger" data-section="" on-tap="openPage_">
           <span i18n-content="basicPageTitle"></span>
           <iron-icon icon="{{arrowState_(basicOpened_)}}" item-icon></iron-icon>

[dpapad, 2016/05/03 01:00:02]

Could this be "[[arrowState_(basicOpened_)]]" instead?

[dschuyler, 2016/05/03 20:48:53]

Done. In separate CL.

         </div>
-        <paper-menu class="menu-content">
+        <paper-menu attr-for-selected="data-section" class="menu-content"
+            data-page="basic" id="basicMenu">
 <if expr="chromeos">
-          <div data-page="basic" data-section="internet" on-tap="openPage_">
+          <div data-section="internet" on-tap="openPage_">
             <iron-icon icon="device:network-wifi" item-icon></iron-icon>
             <span i18n-content="internetPageTitle"></span>
           </div>
 </if>
-          <div data-page="basic" data-section="people" on-tap="openPage_">
+          <div data-section="people" on-tap="openPage_">
             <iron-icon icon="social:people" item-icon></iron-icon>
             <span i18n-content="peoplePageTitle"></span>
           </div>
-          <div data-page="basic" data-section="appearance" on-tap="openPage_">
+          <div data-section="appearance" on-tap="openPage_">
             <iron-icon icon="image:palette" item-icon></iron-icon>
             <span i18n-content="appearancePageTitle"></span>
           </div>
 <if expr="chromeos">
-          <div data-page="basic" data-section="device" on-tap="openPage_">
+          <div data-section="device" on-tap="openPage_">
             <iron-icon icon="hardware:laptop-chromebook" item-icon></iron-icon>
             <span i18n-content="devicePageTitle"></span>
           </div>
 </if>
-          <div data-page="basic" data-section="search" on-tap="openPage_">
+          <div data-section="search" on-tap="openPage_">
             <iron-icon icon="search" item-icon></iron-icon>
             <span i18n-content="searchPageTitle"></span>
           </div>
 <if expr="not chromeos">
-          <div data-page="basic" data-section="defaultBrowser"
-              on-tap="openPage_">
+          <div data-section="defaultBrowser" on-tap="openPage_">
             <iron-icon icon="av:web" item-icon></iron-icon>
             <span i18n-content="defaultBrowser"></span>
           </div>
 </if>
-          <div data-page="basic" data-section="onStartup" on-tap="openPage_">
+          <div data-section="onStartup" on-tap="openPage_">
             <iron-icon icon="icons:power-settings-new" item-icon></iron-icon>
             <span i18n-content="onStartup"></span>
           </div>
         </paper-menu>
       </paper-submenu>
-      <paper-submenu opened="{{advancedOpened_}}">
-        <div class="menu-trigger" data-page="advanced" data-section=""
-            on-tap="openPage_">
+      <paper-submenu id="advancedPage" data-page="advanced">
+        <div class="menu-trigger" data-section="" on-tap="openPage_">
           <span i18n-content="advancedPageTitle"></span>
           <iron-icon icon="{{arrowState_(advancedOpened_)}}" item-icon>
           </iron-icon>
         </div>
-        <paper-menu class="menu-content">
+        <paper-menu attr-for-selected="data-section" class="menu-content"
+            data-page="advanced" id="advancedMenu">
 <if expr="chromeos">
-          <div data-page="advanced" data-section="dateTime" on-tap="openPage_">
+          <div data-section="dateTime" on-tap="openPage_">
             <iron-icon icon="device:access-time" item-icon></iron-icon>
             <span i18n-content="dateTimePageTitle"></span>
           </div>
 </if>
-          <div data-page="advanced" data-section="privacy" on-tap="openPage_">
+          <div data-section="privacy" on-tap="openPage_">
             <iron-icon icon="hardware:security" item-icon></iron-icon>
             <span i18n-content="privacyPageTitle"></span>
           </div>
 <if expr="chromeos">
-          <div data-page="advanced" data-section="bluetooth" on-tap="openPage_">
+          <div data-section="bluetooth" on-tap="openPage_">
             <iron-icon icon="device:bluetooth" item-icon></iron-icon>
             <span i18n-content="bluetoothPageTitle"></span>
           </div>
 </if>
-          <div data-page="advanced" data-section="passwordsAndForms"
-              on-tap="openPage_">
+          <div data-section="passwordsAndForms" on-tap="openPage_">
             <iron-icon icon="icons:assignment" item-icon></iron-icon>
             <span i18n-content="passwordsAndAutofillPageTitle"></span>
           </div>
-          <div data-page="advanced" data-section="languages" on-tap="openPage_">
+          <div data-section="languages" on-tap="openPage_">
             <iron-icon icon="icons:language" item-icon></iron-icon>
             <span i18n-content="languagesPageTitle"></span>
           </div>
-          <div data-page="advanced" data-section="downloads" on-tap="openPage_">
+          <div data-section="downloads" on-tap="openPage_">
             <iron-icon icon="icons:file-download" item-icon></iron-icon>
             <span i18n-content="downloadsPageTitle"></span>
           </div>
-          <div data-page="advanced" data-section="a11y" on-tap="openPage_">
+          <div data-section="a11y" on-tap="openPage_">
             <iron-icon icon="icons:accessibility" item-icon></iron-icon>
             <span i18n-content="a11yPageTitle"></span>
           </div>
 <if expr="not chromeos">
-          <div data-page="advanced" data-section="system" on-tap="openPage_">
+          <div data-section="system" on-tap="openPage_">
             <iron-icon icon="icons:build" item-icon></iron-icon>
             <span i18n-content="systemPageTitle"></span>
           </div>
 </if>
-          <div data-page="advanced" data-section="reset" on-tap="openPage_">
+          <div data-section="reset" on-tap="openPage_">
             <iron-icon icon="icons:restore" item-icon></iron-icon>
             <span i18n-content="resetPageTitle"></span>
           </div>
         </paper-menu>
       </paper-submenu>
       <paper-submenu on-tap="openPage_">
         <div class="menu-trigger">
           <span i18n-content="aboutProgram"></span>
         </div>
       </paper-submenu>
     </paper-menu>
   </template>
   <script src="settings_menu.js"></script>
 </dom-module>