Settings Router Refactor: Remove route.page legacy property.

chrome/browser/resources/settings/advanced_page/advanced_page.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="/a11y_page/a11y_page.html">
 <link rel="import" href="/downloads_page/downloads_page.html">
 <link rel="import" href="/languages_page/languages_page.html">
 <link rel="import" href="/passwords_and_forms_page/passwords_and_forms_page.html">
 <link rel="import" href="/printing_page/printing_page.html">
 <link rel="import" href="/privacy_page/privacy_page.html">
 <link rel="import" href="/reset_page/reset_page.html">
 <link rel="import" href="/settings_page/main_page_behavior.html">
 <link rel="import" href="/settings_page/settings_page_visibility.html">
 <link rel="import" href="/settings_page/settings_router.html">
 <link rel="import" href="/settings_page/settings_section.html">
 <link rel="import" href="/settings_page_css.html">
 <link rel="import" href="/site_settings/constants.html">
 <link rel="import" href="/site_settings/site_settings_category.html">
 
 <if expr="chromeos">
 <link rel="import" href="/bluetooth_page/bluetooth_page.html">
 <link rel="import" href="/date_time_page/date_time_page.html">
 </if>
 
 <if expr="not chromeos">
 <link rel="import" href="/system_page/system_page.html">
 </if>
 
 <dom-module id="settings-advanced-page">
   <template>
     <style include="settings-page-styles"></style>
-    <div data-page="advanced">
+    <div>
 <if expr="chromeos">
       <template is="dom-if" if="[[showPage(pageVisibility.dateTime)]]" restamp>
         <settings-section page-title="$i18n{dateTimePageTitle}"
             current-route="[[currentRoute]]" section="dateTime">
           <settings-date-time-page prefs="{{prefs}}"
               page-visibility="[[pageVisibility.dateTime]]">
           </settings-date-time-page>
         </settings-section>
       </template>
 </if>
@@ skipping 67 matching lines @@
       <template is="dom-if" if="[[showPage(pageVisibility.reset)]]" restamp>
         <settings-section page-title="$i18n{resetPageTitle}"
             current-route="[[currentRoute]]" section="reset">
           <settings-reset-page></settings-reset-page>
         </settings-section>
       </template>
     </div>
   </template>
   <script src="/advanced_page/advanced_page.js"></script>
 </dom-module>