Mojo JS Bindings: revert the Mojo handle toString() method

mojo/edk/js/handle.h

Index: mojo/edk/js/handle.h
diff --git a/mojo/edk/js/handle.h b/mojo/edk/js/handle.h
index c60a3963b558120d4b94405408493d6c98d97012..200b322d44f3c9f7aa24e4dce18580fc9ceec709 100644
--- a/mojo/edk/js/handle.h
+++ b/mojo/edk/js/handle.h
@@ -8,7 +8,6 @@
 #include "base/observer_list.h"
 #include "gin/converter.h"
 #include "gin/handle.h"
-#include "gin/object_template_builder.h"
 #include "gin/wrappable.h"
 #include "mojo/public/cpp/system/core.h"
 
@@ -27,11 +26,6 @@ class HandleWrapper : public gin::Wrappable<HandleWrapper> {
     return gin::CreateHandle(isolate, new HandleWrapper(handle));
   }
 
-  std::string ToString();
-
-  gin::ObjectTemplateBuilder GetObjectTemplateBuilder(v8::Isolate* isolate)
-      override;
-
   mojo::Handle get() const { return handle_.get(); }
   mojo::Handle release() { return handle_.release(); }
   void Close();