[gin] Introduce Wrappable::GetObjectTemplate

gin/function_template.h.pump

 $$ This is a pump file for generating file templates.  Pump is a python
 $$ script that is part of the Google Test suite of utilities.  Description
 $$ can be found here:
 $$
 $$ http://code.google.com/p/googletest/wiki/PumpManual
 $$
 
 #ifndef GIN_FUNCTION_TEMPLATE_H_
 #define GIN_FUNCTION_TEMPLATE_H_
 
@@ skipping 50 matching lines @@
 // JavaScript references in V8.
 
 // This simple base class is used so that we can share a single object template
 // among every CallbackHolder instance.
 class GIN_EXPORT CallbackHolderBase : public Wrappable<CallbackHolderBase> {
  public:
   static WrapperInfo kWrapperInfo;
 
  protected:
   virtual ~CallbackHolderBase() {}
+
+ private:
+  friend class Wrappable<CallbackHolderBase>;
+  static v8::Local<v8::ObjectTemplate> GetObjectTemplate(v8::Isolate* isolate);
 };
 
 template<typename Sig>
 class CallbackHolder : public CallbackHolderBase {
  public:
   CallbackHolder(const base::Callback<Sig>& callback, int flags)
       : callback(callback), flags(flags) {}
   base::Callback<Sig> callback;
   int flags;
  private:
@@ skipping 99 matching lines @@
 
     Invoker<R$for ARG [[, P$(ARG)]]>::Go(&args, holder->callback$for ARG [[, a$(ARG)]]);
   }
 };
 
 ]]
 
 }  // namespace internal
 
 
-// This should be called once per-isolate to initialize the function template
-// system.
-GIN_EXPORT void InitFunctionTemplates(PerIsolateData* isolate_data);
-
-
 // CreateFunctionTemplate creates a v8::FunctionTemplate that will create
 // JavaScript functions that execute a provided C++ function or base::Callback.
 // JavaScript arguments are automatically converted via gin::Converter, as is
 // the return value of the C++ function, if any.
 template<typename Sig>
 v8::Local<v8::FunctionTemplate> CreateFunctionTemplate(
     v8::Isolate* isolate, const base::Callback<Sig> callback,
     int callback_flags = 0) {
   typedef internal::CallbackHolder<Sig> HolderT;
   gin::Handle<HolderT> holder = CreateHandle(
       isolate, new HolderT(callback, callback_flags));
   return v8::FunctionTemplate::New(
       &internal::Dispatcher<Sig>::DispatchToCallback,
       ConvertToV8<internal::CallbackHolderBase*>(isolate, holder.get()));
 }
 
 }  // namespace gin
 
 #endif  // GIN_FUNCTION_TEMPLATE_H_