Move towards event-driven JS on about:sync

chrome/browser/resources/sync_internals/data.js

 // Copyright (c) 2011 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() {
 var dumpToTextButton = $('dump-to-text');
 var dataDump = $('data-dump');
 dumpToTextButton.addEventListener('click', function(event) {
   // TODO(akalin): Add info like Chrome version, OS, date dumped, etc.
 
@@ skipping 146 matching lines @@
     var label = document.createElement('label');
     // Assigning to label.for doesn't work.
     label.setAttribute('for', type);
     label.innerText = type;
     div.appendChild(label);
 
     containerElt.appendChild(div);
   });
 }
 
+function onReceivedListOfTypes(e) {
+  var types = e.details.types;
+  types.sort();
+  createTypesCheckboxes(types);
+  chrome.sync.events.removeEventListener(
+      'onReceivedListOfTypes',
+      onReceivedListOfTypes);
+}
+
 document.addEventListener('DOMContentLoaded', function() {
-  chrome.sync.getListOfTypes(function(types) {
-    types.sort();
-    createTypesCheckboxes(types);
-  });
+  chrome.sync.events.addEventListener(
+      'onReceivedListOfTypes',
+      onReceivedListOfTypes);
+  chrome.sync.requestListOfTypes();
 });
 
 var dumpToFileLink = $('dump-to-file');
 dumpToFileLink.addEventListener('click', function(event) {
   chrome.sync.getAllNodes(triggerDataDownload);
 });
 })();