Add support for AMD to the extensions module system.

extensions/renderer/resources/runtime_custom_bindings.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.
 
 // Custom binding for the runtime API.
 
 var binding = require('binding').Binding.create('runtime');
 
 var messaging = require('messaging');
-var runtimeNatives = requireNative('runtime');
+var runtimeNatives = requireNative('runtime_natives');
 var unloadEvent = require('unload_event');
 var process = requireNative('process');
 var forEach = require('utils').forEach;
 
 var backgroundPage = window;
 var backgroundRequire = require;
 var contextType = process.GetContextType();
 if (contextType == 'BLESSED_EXTENSION' ||
     contextType == 'UNBLESSED_EXTENSION') {
   var manifest = runtimeNatives.GetManifest();
@@ skipping 175 matching lines @@
       request.callback(bg);
     }
     request.callback = null;
   });
 
   bindDirectoryEntryCallback('getPackageDirectoryEntry', apiFunctions);
 });
 
 exports.bindDirectoryEntryCallback = bindDirectoryEntryCallback;
 exports.binding = binding.generate();