Handlify JSObject::SetPrototype method.

src/objects-inl.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 4267 matching lines @@
   if (!transitions()->HasPrototypeTransitions()) {
     return GetHeap()->empty_fixed_array();
   }
   return transitions()->GetPrototypeTransitions();
 }
 
 
 MaybeObject* Map::SetPrototypeTransitions(FixedArray* proto_transitions) {
   MaybeObject* allow_prototype = EnsureHasTransitionArray(this);
   if (allow_prototype->IsFailure()) return allow_prototype;
+  int old_number_of_transitions = NumberOfProtoTransitions();
 #ifdef DEBUG
   if (HasPrototypeTransitions()) {
     ASSERT(GetPrototypeTransitions() != proto_transitions);
     ZapPrototypeTransitions();
   }
 #endif
   transitions()->SetPrototypeTransitions(proto_transitions);
+  SetNumberOfProtoTransitions(old_number_of_transitions);
   return this;
 }
 
 
 bool Map::HasPrototypeTransitions() {
   return HasTransitionArray() && transitions()->HasPrototypeTransitions();
 }
 
 
 TransitionArray* Map::transitions() {
@@ skipping 1873 matching lines @@
 #undef WRITE_UINT32_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_