Implement a module system for the extension bindings JS.

chrome/renderer/resources/extensions/web_request_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 webRequest API.
 
-(function() {
-
-native function GetChromeHidden();
-native function GetUniqueSubEventName(eventName);
+var GetChromeHidden = natives.GetChromeHidden;
+var GetUniqueSubEventName = natives.GetUniqueSubEventName;
 
 var chromeHidden = GetChromeHidden();
 
 // WebRequestEvent object. This is used for special webRequest events with
 // extra parameters. Each invocation of addListener creates a new named
 // sub-event. That sub-event is associated with the extra parameters in the
 // browser process, so that only it is dispatched when the main event occurs
 // matching the extra parameters.
 //
 // Example:
@@ skipping 114 matching lines @@
                 {forIOThread: true});
   });
 
   apiFunctions.setHandleRequest("webRequest.handlerBehaviorChanged",
       function() {
     var args = Array.prototype.slice.call(arguments);
     sendRequest(this.name, args, this.definition.parameters,
                 {forIOThread: true});
   });
 });
-
-})();