Moving prototype transitions into the header of the transition array.

src/objects-debug.cc

Index: src/objects-debug.cc
diff --git a/src/objects-debug.cc b/src/objects-debug.cc
index 6d54d3a4ed182fd036843456d092bd72a033637f..adde6bbd5faff8ec60f1fdb13a452b9f4224b79b 100644
--- a/src/objects-debug.cc
+++ b/src/objects-debug.cc
@@ -1008,7 +1008,6 @@ void NormalizedMapCache::NormalizedMapCacheVerify() {
 
 void Map::ZapTransitions() {
   TransitionArray* transition_array = transitions();
-  if (transition_array == NULL) return;
   MemsetPointer(transition_array->data_start(),
                 GetHeap()->the_hole_value(),
                 transition_array->length());
@@ -1016,7 +1015,7 @@ void Map::ZapTransitions() {
 
 
 void Map::ZapPrototypeTransitions() {
-  FixedArray* proto_transitions = prototype_transitions();
+  FixedArray* proto_transitions = GetPrototypeTransitions();
   MemsetPointer(proto_transitions->data_start(),
                 GetHeap()->the_hole_value(),
                 proto_transitions->length());