Fix setting array length to be ES5 conform.

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 1717 matching lines @@
   // Replace the elements' backing store with fast elements of the given
   // capacity.  Update the length for JSArrays.  Returns the new backing
   // store.
   MUST_USE_RESULT MaybeObject* SetFastElementsCapacityAndLength(
       int capacity,
       int length,
       SetFastElementsCapacityMode set_capacity_mode);
   MUST_USE_RESULT MaybeObject* SetFastDoubleElementsCapacityAndLength(
       int capacity,
       int length);
-  MUST_USE_RESULT MaybeObject* SetSlowElements(Object* length);
 
   // Lookup interceptors are used for handling properties controlled by host
   // objects.
   inline bool HasNamedInterceptor();
   inline bool HasIndexedInterceptor();
 
   // Support functions for v8 api (needed for correct interceptor behavior).
   bool HasRealNamedProperty(String* key);
   bool HasRealElementProperty(uint32_t index);
   bool HasRealNamedCallbackProperty(String* key);
@@ skipping 1231 matching lines @@
   // kRequiresSlowElementsLimit or set_requires_slow_elements() has been called
   // when defining a getter or setter with a number key.
   inline bool requires_slow_elements();
   inline void set_requires_slow_elements();
 
   // Get the value of the max number key that has been added to this
   // dictionary.  max_number_key can only be called if
   // requires_slow_elements returns false.
   inline uint32_t max_number_key();
 
-  // Remove all entries were key is a number and (from <= key && key < to).
-  void RemoveNumberEntries(uint32_t from, uint32_t to);
-
   // Bit masks.
   static const int kRequiresSlowElementsMask = 1;
   static const int kRequiresSlowElementsTagSize = 1;
   static const uint32_t kRequiresSlowElementsLimit = (1 << 29) - 1;
 };
 
 
 template <int entrysize>
 class ObjectHashTableShape {
  public:
@@ skipping 4803 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_