Use GetProperty for getting elements.

src/lookup-inl.h

Index: src/lookup-inl.h
diff --git a/src/lookup-inl.h b/src/lookup-inl.h
index d88f4e47f70dd6bfef316c7123dd9cb0e699f612..5bb1ba107afcf00ed95a5d76be510a6b659bfd72 100644
--- a/src/lookup-inl.h
+++ b/src/lookup-inl.h
@@ -58,11 +58,16 @@ LookupIterator::State LookupIterator::LookupInHolder(Map* const map,
     // Fall through.
     case INTERCEPTOR:
       if (IsElement()) {
+        // TODO(verwaest): Optimize.
         JSObject* js_object = JSObject::cast(holder);
         ElementsAccessor* accessor = js_object->GetElementsAccessor();
         FixedArrayBase* backing_store = js_object->elements();
         number_ = accessor->GetIndexForKey(backing_store, index_);
         if (number_ == kMaxUInt32) return NOT_FOUND;
+        if (accessor->GetAttributes(js_object, index_, backing_store) ==
+            ABSENT) {
+          return NOT_FOUND;
+        }
         property_details_ = accessor->GetDetails(backing_store, number_);
       } else if (holder->IsGlobalObject()) {
         GlobalDictionary* dict = JSObject::cast(holder)->global_dictionary();