Browser side of new ServiceWorker 'sync' event.

content/test/data/service_worker/sync.js

 // Copyright 2014 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.
 
+var code = 404;
+
 this.onfetch = function(event) {
     response = new Response({
-        statusCode: 200,
+        statusCode: code,
         statusText: 'OK',
         method: 'GET',
         headers: {
             'Content-Language': 'fi',
             'Content-Type': 'text/html; charset=UTF-8'
         }
     });
 
     event.respondWith(new Promise(function(r) {
         setTimeout(function() { r(response); }, 5);
     }));
 };
+
+this.onsync = function(event) {
+    code = 200;
+};