MD Settings: Associate suppages with the controls that trigger them.

chrome/browser/resources/settings/device_page/device_page.html

 <link rel="import" href="chrome://resources/html/i18n_behavior.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/neon-animation/neon-animatable.html">
 <link rel="import" href="/controls/settings_dropdown_menu.html">
 <link rel="import" href="/device_page/device_page_browser_proxy.html">
 <link rel="import" href="/device_page/display.html">
 <link rel="import" href="/device_page/keyboard.html">
 <link rel="import" href="/device_page/note.html">
@@ skipping 18 matching lines @@
           <div class="middle">
             [[getPointersTitle_(hasMouse_, hasTouchpad_)]]
           </div>
         </div>
         <div id="keyboardRow" class="settings-box" on-tap="onKeyboardTap_"
             actionable>
           <iron-icon icon="settings:keyboard"></iron-icon>
           <div class="middle">$i18n{keyboardTitle}</div>
         </div>
         <template is="dom-if" if=[[noteAllowed_]]>
-          <div class="settings-box" on-tap="onNoteTap_"
+          <div id="noteRow" class="settings-box" on-tap="onNoteTap_"
               actionable>
             <iron-icon icon="settings:note"></iron-icon>
             <div class="middle">$i18n{noteTitle}</div>
           </div>
         </template>
         <div id="displayRow" class="settings-box" on-tap="onDisplayTap_"
             actionable>
           <iron-icon icon="settings:desktop-windows"></iron-icon>
           <div class="middle">$i18n{displayTitle}</div>
         </div>
       </neon-animatable>
       <template is="dom-if" name="pointers">
         <settings-subpage
+            associated-control="[[$$('#pointersRow')]]"
             page-title="[[getPointersTitle_(hasMouse_, hasTouchpad_)]]">
           <settings-pointers prefs="{{prefs}}"
               has-mouse="[[hasMouse_]]" has-touchpad="[[hasTouchpad_]]">
           </settings-pointers>
         </settings-subpage>
       </template>
       <template is="dom-if" name="keyboard">
-        <settings-subpage page-title="$i18n{keyboardTitle}">
+        <settings-subpage
+            associated-control="[[$$('#keyboardRow')]]"
+            page-title="$i18n{keyboardTitle}">
           <settings-keyboard prefs="{{prefs}}"></settings-keyboard>
         </settings-subpage>
       </template>
       <template is="dom-if" if=[[noteAllowed_]]>
         <template is="dom-if" name="note">
-          <settings-subpage page-title="$i18n{noteTitle}">
+          <settings-subpage
+              associated-control="[[$$('#noteRow')]]"
+              page-title="$i18n{noteTitle}">
             <settings-note prefs="{{prefs}}" current-route="{{currentRoute}}">
             </settings-note>
           </settings-subpage>
         </template>
       </template>
       <template is="dom-if" name="display">
-        <settings-subpage page-title="$i18n{displayTitle}">
+        <settings-subpage
+            associated-control="[[$$('#displayRow')]]"
+            page-title="$i18n{displayTitle}">
           <settings-display></settings-display>
         </settings-subpage>
       </template>
     </settings-animated-pages>
   </template>
   <script src="device_page.js"></script>
 </dom-module>