Free up 11 bits in fast-mode PropertyDetails by removing the enumeration-index.

test/cctest/test-alloc.cc

 // Copyright 2012 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 124 matching lines @@
       FACTORY->NewStringFromAscii(Vector<const char>("get", 3));
   ASSERT(instance_descriptors->IsEmpty());
 
   Handle<DescriptorArray> new_descriptors = FACTORY->NewDescriptorArray(0, 1);
 
   v8::internal::DescriptorArray::WhitenessWitness witness(*new_descriptors);
   map->set_instance_descriptors(*new_descriptors);
 
   CallbacksDescriptor d(*name,
                         *foreign,
-                        static_cast<PropertyAttributes>(0),
-                        v8::internal::PropertyDetails::kInitialIndex);
+                        static_cast<PropertyAttributes>(0));
   map->AppendDescriptor(&d, witness);
 
   // Add the Foo constructor the global object.
   env->Global()->Set(v8::String::New("Foo"), v8::Utils::ToLocal(function));
   // Call the accessor through JavaScript.
   v8::Handle<v8::Value> result =
       v8::Script::Compile(v8::String::New("(new Foo).get"))->Run();
   CHECK_EQ(42, result->Int32Value());
   env->Exit();
 }
@@ skipping 63 matching lines @@
         blocks[index] = blocks.RemoveLast();
       } else {
         blocks.RemoveLast();
       }
     }
   }
 
   code_range->TearDown();
   delete code_range;
 }