Promoting elements transitions to their own field.

src/property-details.h

 // 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 45 matching lines @@
 // A copy of this is in mirror-debugger.js.
 enum PropertyType {
   NORMAL                    = 0,  // only in slow mode
   FIELD                     = 1,  // only in fast mode
   CONSTANT_FUNCTION         = 2,  // only in fast mode
   CALLBACKS                 = 3,
   HANDLER                   = 4,  // only in lookup results, not in descriptors
   INTERCEPTOR               = 5,  // only in lookup results, not in descriptors
   // All properties before MAP_TRANSITION are real.
   MAP_TRANSITION            = 6,  // only in fast mode
-  ELEMENTS_TRANSITION       = 7,
-  CONSTANT_TRANSITION       = 8,  // only in fast mode
-  NULL_DESCRIPTOR           = 9,  // only in fast mode
+  CONSTANT_TRANSITION       = 7,  // only in fast mode
+  NULL_DESCRIPTOR           = 8,  // only in fast mode
   // There are no IC stubs for NULL_DESCRIPTORS. Therefore,
   // NULL_DESCRIPTOR can be used as the type flag for IC stubs for
   // nonexistent properties.
   NONEXISTENT = NULL_DESCRIPTOR
 };
 
 
 // PropertyDetails captures type and attributes for a property.
 // They are used both in property dictionaries and instance descriptors.
 class PropertyDetails BASE_EMBEDDED {
@@ skipping 44 matching lines @@
 
   static const int kInitialIndex = 1;
 
  private:
   uint32_t value_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROPERTY_DETAILS_H_