No longer start BG mode until a BackgroundContents is loaded

chrome/test/data/extensions/api_test/app_background_page/common/common.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.
 var scriptMessageEvent;
 var pageToScriptTunnel;
 var scriptToPageTunnel;
 
 function setStatus(status) {
   document.getElementById('status').innerText = status;
 }
 
 function setupScriptTunnel() {
   scriptMessageEvent = document.createEvent("Event");
@@ skipping 36 matching lines @@
 
 function notifyCounterError() {
   pageToScriptTunnel.innerText = JSON.stringify(messageData(arguments));
   pageToScriptTunnel.dispatchEvent(scriptMessageEvent);
 }
 
 function notifyBackgroundPageClosing() {
   pageToScriptTunnel.innerText = JSON.stringify(messageData(arguments));
   pageToScriptTunnel.dispatchEvent(scriptMessageEvent);
 }
+
+function notifyBackgroundPageClosed() {
+  pageToScriptTunnel.innerText = JSON.stringify(messageData(arguments));
+  pageToScriptTunnel.dispatchEvent(scriptMessageEvent);
+}