Add tests for console messages of waitUntil() and respondWith()

content/test/data/service_worker/fetch_event_rejected.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.
 
-this.onactivate = function(event) {
-    event.waitUntil(new Promise(function(resolve, reject) {
-        setTimeout(reject, 5);
+this.onfetch = function(event) {
+    event.respondWith(new Promise(function(resolve, reject) {
+        setTimeout(function() { reject("Rejecting respondWith promise"); }, 5);
     }));
 };