Do not waste space for the fast-case elements backing storage for ...

src/parser.h

 // Copyright 2006-2008 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 150 matching lines @@
                              int start_position,
                              int end_position,
                              bool is_expression);
 
 
 // Support for handling complex values (array and object literals) that
 // can be fully handled at compile time.
 class CompileTimeValue: public AllStatic {
  public:
   enum Type {
-    OBJECT_LITERAL,
+    OBJECT_LITERAL_FAST_ELEMENTS,
+    OBJECT_LITERAL_SLOW_ELEMENTS,
     ARRAY_LITERAL
   };
 
   static bool IsCompileTimeValue(Expression* expression);
 
   // Get the value as a compile time value.
   static Handle<FixedArray> GetValue(Expression* expression);
 
   // Get the type of a compile time value returned by GetValue().
   static Type GetType(Handle<FixedArray> value);
 
   // Get the elements array of a compile time value returned by GetValue().
   static Handle<FixedArray> GetElements(Handle<FixedArray> value);
 
  private:
   static const int kTypeSlot = 0;
   static const int kElementsSlot = 1;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompileTimeValue);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_PARSER_H_