Fix a bug in for/in iteration of arguments objects.

src/objects.h

 // Copyright 2011 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 2752 matching lines @@
   // Attempt to shrink the dictionary after deletion of key.
   MUST_USE_RESULT MaybeObject* Shrink(Key key);
 
   // Returns the number of elements in the dictionary filtering out properties
   // with the specified attributes.
   int NumberOfElementsFilterAttributes(PropertyAttributes filter);
 
   // Returns the number of enumerable elements in the dictionary.
   int NumberOfEnumElements();
 
+  enum SortMode { UNSORTED, SORTED };
   // Copies keys to preallocated fixed array.
-  void CopyKeysTo(FixedArray* storage, PropertyAttributes filter);
+  void CopyKeysTo(FixedArray* storage,
+                  PropertyAttributes filter,
+                  SortMode sort_mode);
   // Fill in details for properties into storage.
-  void CopyKeysTo(FixedArray* storage);
+  void CopyKeysTo(FixedArray* storage, SortMode sort_mode);
 
   // Accessors for next enumeration index.
   void SetNextEnumerationIndex(int index) {
     this->fast_set(this, kNextEnumerationIndexIndex, Smi::FromInt(index));
   }
 
   int NextEnumerationIndex() {
     return Smi::cast(FixedArray::get(kNextEnumerationIndexIndex))->value();
   }
 
@@ skipping 4346 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_