Refactor about:sync's events framework

chrome/browser/resources/sync_internals/about.js

 // Copyright (c) 2012 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.
 
 function highlightIfChanged(node, oldVal, newVal) {
   function clearHighlight() {
     this.removeAttribute('highlighted');
   }
 
   var oldStr = oldVal.toString();
@@ skipping 16 matching lines @@
 function refreshAboutInfo(aboutInfo) {
   chrome.sync.aboutInfo = aboutInfo;
   var aboutInfoDiv = $('aboutInfo');
   jstProcess(new JsEvalContext(aboutInfo), aboutInfoDiv);
 }
 
 function onLoad() {
   $('status-data').hidden = true;
   chrome.sync.getAboutInfo(refreshAboutInfo);
 
-  chrome.sync.onServiceStateChanged.addListener(function() {
-    chrome.sync.getAboutInfo(refreshAboutInfo);
-  });
+  chrome.sync.events.addEventListener(
+      'onServiceStateChanged',
+      function(e) {
+        chrome.sync.getAboutInfo(refreshAboutInfo);
+      });
 
   var dumpStatusButton = $('dump-status');
   dumpStatusButton.addEventListener('click', function(event) {
     var aboutInfo = chrome.sync.aboutInfo;
     if (!$('include-ids').checked) {
       aboutInfo.details = chrome.sync.aboutInfo.details.filter(function(el) {
         return !el.is_sensitive;
       });
     }
     var data = '';
@@ skipping 18 matching lines @@
     // First remove any characters before the '{'.
     var data = $('status-text').value;
     var firstBrace = data.indexOf('{');
     if (firstBrace < 0) {
       $('status-text').value = 'Invalid sync status dump.';
       return;
     }
     data = data.substr(firstBrace);
 
     // Remove listeners to prevent sync events from overwriting imported data.
-    chrome.sync.onServiceStateChanged.removeListeners();
+    chrome.sync.events.removeEventListener(
+        'onServiceStateChanged',
+        refreshAboutInfo);
 
     var aboutInfo = JSON.parse(data);
     refreshAboutInfo(aboutInfo);
   });
 }
 
 document.addEventListener('DOMContentLoaded', onLoad, false);
 })();