MD Settings: show restart button when user toggles metrics reporting

chrome/browser/resources/settings/privacy_page/privacy_page.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-privacy-page' is the settings page containing privacy and
  * security settings.
  */
 Polymer({
@@ skipping 15 matching lines @@
       notify: true,
     },
 
     /**
      * Dictionary defining page visibility.
      * @type {!PrivacyPageVisibility}
      */
     pageVisibility: Object,
 
 <if expr="_google_chrome and not chromeos">
     /** @type {MetricsReporting} */

[dpapad, 2016/11/03 01:32:38]

?MetricsReporting

[Dan Beam, 2016/11/03 01:38:32]

this isn't initially null, it's undefined

/** @type {Thing} */
var blah;
this.getBlah().then(function(blah) {
  blah = newBlah;
});

doesn't have a ? and some people put ! even though it's technically |undefined
until success

     metricsReporting_: Object,
+
+    showRestart_: Boolean,
 </if>
 
     /** @private */
     showClearBrowsingDataDialog_: Boolean,
   },
 
 <if expr="_google_chrome">
   observers: [
     'updateSpellingService_(prefs.spellcheck.use_spelling_service.value)',
   ],
@@ skipping 59 matching lines @@
     var browserProxy = settings.PrivacyPageBrowserProxyImpl.getInstance();
     var enabled = this.$.metricsReportingCheckbox.checked;
     browserProxy.setMetricsReportingEnabled(enabled);
   },
 
   /**
    * @param {!MetricsReporting} metricsReporting
    * @private
    */
   setMetricsReporting_: function(metricsReporting) {
+    if (this.metricsReporting_) {
+      // TODO(dbeam): hide if changed back to the value Chrome started with.

[dpapad, 2016/11/03 01:32:38]

Eh, is that too hard to do now? Just need an extra boolean, right?

[Dan Beam, 2016/11/03 01:38:32]

to do correctly, we need to do this on chrome startup from the metrics code

see: how GPU acceleration works

+      this.showRestart_ = true;
+    }
     this.metricsReporting_ = metricsReporting;
   },
+
+  /** @private */
+  onRestartTap_: function() {
+    settings.LifetimeBrowserProxyImpl.getInstance().restart();
+  },
 </if>
 
 <if expr="_google_chrome">
   /** @private */
   updateSpellingService_: function() {
     this.$.spellingServiceToggleButton.checked =
         this.get('prefs.spellcheck.use_spelling_service.value');
   },
 
   /** @private */
   onUseSpellingServiceTap_: function() {
     this.set('prefs.spellcheck.use_spelling_service.value',
         this.$.spellingServiceToggleButton.checked);
   },
 </if>
 
   /**
    * The sub-page title for the site or content settings.
    * @return {string}
    * @private
    */
   siteSettingsPageTitle_: function() {
     return loadTimeData.getBoolean('enableSiteSettings') ?
         loadTimeData.getString('siteSettings') :
         loadTimeData.getString('contentSettings');
   },
 });