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

chrome/renderer/native_handler.cc

 // 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.
 
 #include "chrome/renderer/native_handler.h"
 
 #include "base/memory/linked_ptr.h"
 #include "base/logging.h"
 #include "v8/include/v8.h"
 
 NativeHandler::NativeHandler()
-    : object_template_(v8::ObjectTemplate::New()) {
+    : object_template_(
+        v8::Persistent<v8::ObjectTemplate>::New(v8::ObjectTemplate::New())) {
 }
 
-NativeHandler::~NativeHandler() {}
+NativeHandler::~NativeHandler() {
+  object_template_.Dispose();
+}
 
 v8::Handle<v8::Object> NativeHandler::NewInstance() {
   return object_template_->NewInstance();
 }
 
 // static
 v8::Handle<v8::Value> NativeHandler::Router(const v8::Arguments& args) {
   HandlerFunction* handler_function = static_cast<HandlerFunction*>(
       args.Data().As<v8::External>()->Value());
   return handler_function->Run(args);
@@ skipping 10 matching lines @@
           v8::External::New(function.get()));
   object_template_->Set(name.c_str(), function_template);
 }
 
 void NativeHandler::RouteStaticFunction(const std::string& name,
                                         const HandlerFunc handler_func) {
   v8::Handle<v8::FunctionTemplate> function_template =
       v8::FunctionTemplate::New(handler_func, v8::External::New(this));
   object_template_->Set(name.c_str(), function_template);
 }