Introduce v8::Object::CreateDataProperty

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index ce7f7853bb7364882e7f02fdf49d3daca477b936..d708a0ecdd3a81bd93bfac42446d79e4351261e5 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -2143,10 +2143,12 @@ class JSObject: public JSReceiver {
   // Check whether this object references another object
   bool ReferencesObject(Object* obj);
 
-  // Disalow further properties to be added to the object.
+  // Disalow further properties to be added to the oject.
   MUST_USE_RESULT static MaybeHandle<Object> PreventExtensions(
       Handle<JSObject> object);
 
+  bool IsExtensible();
+
   // ES5 Object.seal
   MUST_USE_RESULT static MaybeHandle<Object> Seal(Handle<JSObject> object);