Reland of Remove GetAttributes from the mix to avoid another virtual dispatch.

src/lookup-inl.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_LOOKUP_INL_H_
 #define V8_LOOKUP_INL_H_
 
 #include "src/lookup.h"
 
 namespace v8 {
@@ skipping 54 matching lines @@
           property_details_ = PropertyDetails(attributes, v8::internal::DATA, 0,
                                               PropertyCellType::kNoCell);
         } else {
           JSObject* js_object = JSObject::cast(holder);
           if (js_object->elements() == isolate()->heap()->empty_fixed_array()) {
             return NOT_FOUND;
           }
 
           ElementsAccessor* accessor = js_object->GetElementsAccessor();
           FixedArrayBase* backing_store = js_object->elements();
-          number_ = accessor->GetIndexForKey(backing_store, index_);
+          number_ = accessor->GetIndexForKey(js_object, 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();
         int number = dict->FindEntry(name_);
         if (number == GlobalDictionary::kNotFound) return NOT_FOUND;
         number_ = static_cast<uint32_t>(number);
         DCHECK(dict->ValueAt(number_)->IsPropertyCell());
         PropertyCell* cell = PropertyCell::cast(dict->ValueAt(number_));
         if (cell->value()->IsTheHole()) return NOT_FOUND;
@@ skipping 43 matching lines @@
     default:
       return NOT_FOUND;
   }
   UNREACHABLE();
   return state_;
 }
 }
 }  // namespace v8::internal
 
 #endif  // V8_LOOKUP_INL_H_