[gin] Introduce Wrappable::GetObjectTemplate

gin/function_template.cc

 // Copyright 2013 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 "gin/function_template.h"
 
-#include "gin/per_isolate_data.h"
+#include "gin/object_template_builder.h"
 
 namespace gin {
 
-WrapperInfo internal::CallbackHolderBase::kWrapperInfo = { kEmbedderNativeGin };
+namespace internal {
 
-void InitFunctionTemplates(PerIsolateData* isolate_data) {
-  if (!isolate_data->GetObjectTemplate(
-          &internal::CallbackHolderBase::kWrapperInfo).IsEmpty()) {
-    return;
-  }
+WrapperInfo CallbackHolderBase::kWrapperInfo = { kEmbedderNativeGin };
 
-  v8::Handle<v8::ObjectTemplate> templ(
-      v8::ObjectTemplate::New(isolate_data->isolate()));
-  templ->SetInternalFieldCount(kNumberOfInternalFields);
-  isolate_data->SetObjectTemplate(&internal::CallbackHolderBase::kWrapperInfo,
-                                  templ);
+v8::Local<v8::ObjectTemplate> CallbackHolderBase::GetObjectTemplate(
+    v8::Isolate* isolate) {
+  return ObjectTemplateBuilder(isolate).Build();
 }
 
+}  // namespace internal
+
 }  // namespace gin