Implement a module system for the extension bindings JS.

chrome/renderer/resources/extensions/app.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 chrome = chrome || {};
-(function() {
-  native function GetChromeHidden();
-  native function GetIsInstalled();
-  native function Install();
-  native function GetDetails();
-  native function GetDetailsForFrame();
-  native function GetAppNotifyChannel();
+  var natives = requireNative('app');
+  var GetIsInstalled = natives.GetIsInstalled;
+  var Install = natives.Install;
+  var GetDetails = natives.GetDetails;
+  var GetDetailsForFrame = natives.GetDetailsForFrame;
+  var GetAppNotifyChannel = natives.GetAppNotifyChannel;
 
-  var chromeHidden = GetChromeHidden();
+  var chromeHidden = requireNative('chrome_hidden').GetChromeHidden();
   var callbacks = {};
   var nextCallbackId = 1;
 
   chrome.app = new function() {
     this.__defineGetter__('isInstalled', GetIsInstalled);
     this.install = Install;
     this.getDetails = GetDetails;
     this.getDetailsForFrame = GetDetailsForFrame;
   }();
 
   chrome.appNotifications = new function() {
     this.getChannel = function(clientId, callback) {
       var callbackId = 0;
       if (callback) {
         callbackId = nextCallbackId++;
         callbacks[callbackId] = callback;
       }
       GetAppNotifyChannel(clientId, callbackId);
     };
   }();
 
   chromeHidden.app = {};
   chromeHidden.app.onGetAppNotifyChannelResponse =
       function(channelId, error, callbackId) {
     if (callbackId) {
       callbacks[callbackId](channelId, error);
       delete callbacks[callbackId];
     }
   };
-})();