Gin: Make it easier to implement Wrappable

gin/wrappable.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/wrappable.h"
 
 #include "base/logging.h"
 #include "gin/per_isolate_data.h"
 
 namespace gin {
 
-Wrappable::Wrappable() {
+WrapperInfo* WrappableTraitsTest::GetWrapperInfo() {
+  return &WrappableTraits<WrappableTraitsTest>::kWrapperInfo;
 }
 
-Wrappable::~Wrappable() {
+WrappableBase::WrappableBase() {
+}
+
+WrappableBase::~WrappableBase() {
   wrapper_.Reset();
 }
 
-v8::Handle<v8::Object> Wrappable::GetWrapper(v8::Isolate* isolate) {
+v8::Handle<v8::Object> WrappableBase::GetWrapper(v8::Isolate* isolate) {
   if (wrapper_.IsEmpty())
     CreateWrapper(isolate);
   return v8::Local<v8::Object>::New(isolate, wrapper_);
 }
 
-void Wrappable::WeakCallback(
-    const v8::WeakCallbackData<v8::Object, Wrappable>& data) {
-  Wrappable* wrappable = data.GetParameter();
+void WrappableBase::WeakCallback(
+    const v8::WeakCallbackData<v8::Object, WrappableBase>& data) {
+  WrappableBase* wrappable = data.GetParameter();
   wrappable->wrapper_.Reset();
   delete wrappable;
 }
 
-v8::Handle<v8::Object> Wrappable::CreateWrapper(v8::Isolate* isolate) {
+v8::Handle<v8::Object> WrappableBase::CreateWrapper(v8::Isolate* isolate) {
   WrapperInfo* info = GetWrapperInfo();
   PerIsolateData* data = PerIsolateData::From(isolate);
   v8::Local<v8::ObjectTemplate> templ = data->GetObjectTemplate(info);
   CHECK(!templ.IsEmpty());  // Don't forget to register an object template.
   CHECK_EQ(kNumberOfInternalFields, templ->InternalFieldCount());
   v8::Handle<v8::Object> wrapper = templ->NewInstance();
   wrapper->SetAlignedPointerInInternalField(kWrapperInfoIndex, info);
   wrapper->SetAlignedPointerInInternalField(kEncodedValueIndex, this);
   wrapper_.Reset(isolate, wrapper);
   wrapper_.SetWeak(this, WeakCallback);
   return wrapper;
 }
 
 }  // namespace gin