Implement a module system for the extension bindings JS.

chrome/renderer/resources/extensions/content_settings_custom_bindings.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.
 
 // Custom bindings for the contentSettings API.
 
 (function() {
 
-native function GetChromeHidden();
-
-var chromeHidden = GetChromeHidden();
+var chromeHidden = requireNative('chrome_hidden').GetChromeHidden();
 
 chromeHidden.registerCustomType('ContentSetting', function(typesAPI) {
   var sendRequest = typesAPI.sendRequest;
 
   function extendSchema(schema) {
     var extendedSchema = schema.slice();
     extendedSchema.unshift({'type': 'string'});
     return extendedSchema;
   }
 
@@ skipping 27 matching lines @@
           'contentSettings.getResourceIdentifiers',
           [contentType, callback],
           extendSchema(schema));
     };
   }
 
   return ContentSetting;
 });
 
 })();