Remove elements transitions from the transition array.

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 4239 matching lines @@
 }
 
 
 bool Map::HasTransitionArray() {
   Object* object = READ_FIELD(this, kTransitionsOrBackPointerOffset);
   return object->IsTransitionArray();
 }
 
 
 Map* Map::elements_transition_map() {
-  return transitions()->elements_transition();
+  int index = transitions()->Search(GetHeap()->elements_transition_symbol());
+  return transitions()->GetTarget(index);
 }
 
 
 bool Map::CanHaveMoreTransitions() {
   if (!HasTransitionArray()) return true;
   return FixedArray::SizeFor(transitions()->length() +
                              TransitionArray::kTransitionSize)
       <= Page::kMaxNonCodeHeapObjectSize;
 }
 
@@ skipping 10 matching lines @@
   transitions()->SetTarget(transition_index, target);
 }
 
 
 Map* Map::GetTransition(int transition_index) {
   return transitions()->GetTarget(transition_index);
 }
 
 
 MaybeObject* Map::set_elements_transition_map(Map* transitioned_map) {
-  MaybeObject* allow_elements = EnsureHasTransitionArray(this);
-  if (allow_elements->IsFailure()) return allow_elements;
-  transitions()->set_elements_transition(transitioned_map);
-  return this;
+  TransitionArray* transitions;
+  MaybeObject* maybe_transitions = AddTransition(
+      GetHeap()->elements_transition_symbol(),
+      transitioned_map,
+      FULL_TRANSITION);
+  if (!maybe_transitions->To(&transitions)) return maybe_transitions;
+  set_transitions(transitions);
+  return transitions;
 }
 
 
 FixedArray* Map::GetPrototypeTransitions() {
   if (!HasTransitionArray()) return GetHeap()->empty_fixed_array();
   if (!transitions()->HasPrototypeTransitions()) {
     return GetHeap()->empty_fixed_array();
   }
   return transitions()->GetPrototypeTransitions();
 }
@@ skipping 1919 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_