Introduce chrome.shell.createWindow stub API for app_shell

chrome/common/extensions/docs/examples/apps/calculator/app/controller.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.
  **/
 
 // Checking for "chrome.app.runtime" availability allows this Chrome app code to
 // be tested in a regular web page (like tests/manual.html). Checking for
 // "chrome" and "chrome.app" availability further allows this code to be tested
 // in non-Chrome browsers, which is useful for example to test touch support
 // with a non-Chrome touch device.
 if (typeof chrome !== 'undefined' && chrome.app && chrome.app.runtime) {
+  // Compatibility for running under app_shell, which does not have app.window.
+  var createWindow =
+      chrome.shell ? chrome.shell.createWindow : chrome.app.window.create;
+
   var showCalculatorWindow = function () {
-    chrome.app.window.create('calculator.html', {
+    createWindow('calculator.html', {
       innerBounds: {
         width: 243, minWidth: 243, maxWidth: 243,
         height: 380, minHeight: 380, maxHeight: 380
       },
       id: 'calculator'
     }, function(appWindow) {
       appWindow.contentWindow.onload = function() {
         new Controller(new Model(9), new View(appWindow.contentWindow));
       };
     });
@@ skipping 72 matching lines @@
     operand: this.getUpdatedValue_(before, after, 'operand', !before.operator)
   });
   return !before.accumulator;
 }
 
 /** @private */
 Controller.prototype.getUpdatedValue_ = function(before, after, key, zero) {
   var value = (typeof after[key] !== 'undefined') ? after[key] : before[key];
   return zero ? (value || '0') : value;
 }