Make app_custom_bindings.js lazily evaluated so it doesn't execute on every page load.

chrome/renderer/native_handler.h

 // 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.
 
 #ifndef CHROME_RENDERER_NATIVE_HANDLER_H_
 #define CHROME_RENDERER_NATIVE_HANDLER_H_
 #pragma once
 
 #include "base/bind.h"
 #include "base/memory/linked_ptr.h"
@@ skipping 31 matching lines @@
   void RouteFunction(const std::string& name,
                      const HandlerFunction& handler_function);
 
   void RouteStaticFunction(const std::string& name,
                            const HandlerFunc handler_func);
 
  private:
   static v8::Handle<v8::Value> Router(const v8::Arguments& args);
 
   std::vector<linked_ptr<HandlerFunction> > handler_functions_;
-  v8::Handle<v8::ObjectTemplate> object_template_;
+  v8::Persistent<v8::ObjectTemplate> object_template_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeHandler);
 };
 
 #endif  // CHROME_RENDERER_NATIVE_HANDLER_H_