[gin] Introduce Wrappable::GetObjectTemplate

mojo/apps/js/bindings/gl/module.cc

Index: mojo/apps/js/bindings/gl/module.cc
diff --git a/mojo/apps/js/bindings/gl/module.cc b/mojo/apps/js/bindings/gl/module.cc
index abc0706284cb9c6211a7f167eb15e340a50af9f4..adf5ac3342cb1b1ee093d55c60999df85274c979 100644
--- a/mojo/apps/js/bindings/gl/module.cc
+++ b/mojo/apps/js/bindings/gl/module.cc
@@ -39,13 +39,9 @@ v8::Local<v8::ObjectTemplate> GetModuleTemplate(v8::Isolate* isolate) {
     templ = gin::ObjectTemplateBuilder(isolate)
         .SetMethod("Context", CreateContext)
         .Build();
-    templ->SetInternalFieldCount(gin::kNumberOfInternalFields);
     data->SetObjectTemplate(&kWrapperInfo, templ);
   }
 
-  Context::GetObjectTemplate(isolate);
-  Opaque::GetObjectTemplate(isolate);
-
   return templ;
 }