Use LookupIterator in GetOldValue

src/objects.h

 // Copyright 2012 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_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 2001 matching lines @@
   // be represented as a double and not a Smi.
   bool ShouldConvertToFastDoubleElements(bool* has_smi_only_elements);
 
   // Computes the new capacity when expanding the elements of a JSObject.
   static int NewElementsCapacity(int old_capacity) {
     // (old_capacity + 50%) + 16
     return old_capacity + (old_capacity >> 1) + 16;
   }
 
   // These methods do not perform access checks!
-  MUST_USE_RESULT static MaybeHandle<AccessorPair> GetOwnElementAccessorPair(
-      Handle<JSObject> object, uint32_t index);
-
   static void UpdateAllocationSite(Handle<JSObject> object,
                                    ElementsKind to_kind);
 
   enum SetFastElementsCapacitySmiMode {
     kAllowSmiElements,
     kForceSmiElements,
     kDontAllowSmiElements
   };
 
   static Handle<FixedArray> SetFastElementsCapacity(
@@ skipping 8818 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_