MD Settings; Lazy instantiate Clear Browsing Data dialog.

chrome/browser/resources/settings/privacy_page/privacy_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/polymer/v1_0/iron-flex-layout/classes/iron-flex-layout.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/neon-animation/neon-animatable.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
 <link rel="import" href="chrome://md-settings/clear_browsing_data_dialog/clear_browsing_data_dialog.html">
 <link rel="import" href="chrome://md-settings/controls/settings_checkbox.html">
 <link rel="import" href="chrome://md-settings/settings_page/settings_animated_pages.html">
 <link rel="import" href="chrome://md-settings/settings_page/settings_subpage.html">
 <link rel="import" href="chrome://md-settings/settings_shared_css.html">
 <link rel="import" href="chrome://md-settings/site_settings/all_sites.html">
 <link rel="import" href="chrome://md-settings/site_settings/constants.html">
 <link rel="import" href="chrome://md-settings/site_settings_page/site_settings_page.html">
 
 <if expr="use_nss_certs">
 <link rel="import" href="chrome://md-settings/certificate_manager_page/certificate_manager_page.html">
 </if>
 <if expr="is_win or is_macosx">
 <link rel="import" href="chrome://md-settings/privacy_page/privacy_page_browser_proxy.html">
 </if>
 
 <dom-module id="settings-privacy-page">
   <template>
     <style include="settings-shared"></style>
+    <template is="dom-if" if="[[showClearBrowsingDataDialog_]]" restamp>
+      <settings-clear-browsing-data-dialog prefs="{{prefs}}"
+          on-iron-overlay-closed="onIronOverlayClosed_">
+      </settings-clear-browsing-data-dialog>
+    </template>
     <settings-animated-pages id="pages" current-route="{{currentRoute}}"
         section="privacy">
       <neon-animatable id="main">
-        <settings-clear-browsing-data-dialog prefs="{{prefs}}">
-        </settings-clear-browsing-data-dialog>
         <div class="settings-box block first">
           <p class="privacy-explanation"
               i18n-values=".innerHTML:improveBrowsingExperience">
           </p>
           <settings-checkbox
               pref="{{prefs.alternate_error_pages.enabled}}"
               i18n-values="label:linkDoctorPref">
           </settings-checkbox>
           <settings-checkbox
               pref="{{prefs.search.suggest_enabled}}"
@@ skipping 178 matching lines @@
       <template is="dom-if" name="site-details">
         <settings-subpage
             page-title="[[i18n('siteSettingsSiteDetailsPageTitle')]]">
           <site-details site="[[selectedSite]]"></site-details>
         </settings-subpage>
       </template>
     </settings-animated-pages>
   </template>
   <script src="privacy_page.js"></script>
 </dom-module>