[Extensions] Have Binding inherit from null proto

extensions/renderer/resources/binding.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.
 
 var Event = require('event_bindings').Event;
 var forEach = require('utils').forEach;
 var GetAvailability = requireNative('v8_context').GetAvailability;
 var exceptionHandler = require('uncaught_exception_handler');
 var lastError = require('lastError');
 var logActivity = requireNative('activityLogger');
@@ skipping 161 matching lines @@
   customType.prototype = new CustomBindingsObject();
   customType.prototype.setSchema(type);
   return customType;
 }
 
 var platform = getPlatform();
 
 function Binding(apiName) {
   this.apiName_ = apiName;
   this.apiFunctions_ = new APIFunctions(apiName);
-  this.customEvent_ = null;
   this.customHooks_ = [];
 };
 
 Binding.create = function(apiName) {
   return new Binding(apiName);
 };
 
 Binding.prototype = {
+  // Sneaky workaround for Object.prototype getters/setters - our prototype
+  // isn't Object.prototype. SafeBuiltins (e.g. $Object.hasOwnProperty())
+  // should still work.
+  __proto__: null,
+
+  // Forward-declare properties.
+  apiName_: undefined,
+  apiFunctions_: undefined,
+  customEvent_: undefined,
+  customHooks_: undefined,
+
   // The API through which the ${api_name}_custom_bindings.js files customize
   // their API bindings beyond what can be generated.
   //
   // There are 2 types of customizations available: those which are required in
   // order to do the schema generation (registerCustomEvent and
   // registerCustomType), and those which can only run after the bindings have
   // been generated (registerCustomHook).
 
   // Registers a custom event type for the API identified by |namespace|.
   // |event| is the event's constructor.
@@ skipping 338 matching lines @@
                     availability.message);
       return;
     }
 
     this.runHooks_(mod, schema);
     return mod;
   }
 };
 
 exports.$set('Binding', Binding);