[Extensions] More bindings hardening

chrome/renderer/resources/extensions/content_setting.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 binding for the contentSettings API.
 
 var sendRequest = require('sendRequest').sendRequest;
 var validate = require('schemaUtils').validate;
 
 function extendSchema(schema) {
@@ skipping 30 matching lines @@
     var schema =
         this.functionSchemas.getResourceIdentifiers.definition.parameters;
     validate([callback], schema);
     return sendRequest(
         'contentSettings.getResourceIdentifiers',
         [contentType, callback],
         extendSchema(schema));
   };
 }
 
-exports.ContentSetting = ContentSetting;
+exports.$set('ContentSetting', ContentSetting);