Use JSObject::SetMapAndElements rather than set_map + set_elements.

src/api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3718 matching lines @@
                                   int length) {
   i::Isolate* isolate = object->GetIsolate();
   i::Handle<i::ExternalArray> array =
       isolate->factory()->NewExternalArray(length, array_type, data);
 
   i::Handle<i::Map> external_array_map =
       i::JSObject::GetElementsTransitionMap(
           object,
           GetElementsKindFromExternalArrayType(array_type));
 
-  object->set_map(*external_array_map);
-  object->set_elements(*array);
+  i::JSObject::SetMapAndElements(object, external_array_map, array);
 }
 
 }  // namespace
 
 
 void v8::Object::SetIndexedPropertiesToPixelData(uint8_t* data, int length) {
   i::Isolate* isolate = Utils::OpenHandle(this)->GetIsolate();
   ON_BAILOUT(isolate, "v8::SetElementsToPixelData()", return);
   ENTER_V8(isolate);
   i::HandleScope scope(isolate);
@@ skipping 3902 matching lines @@
   Isolate* isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 } }  // namespace v8::internal