Moved lastadded from DescriptorArray to Map. Renamed kLastAdded to kEnumCache.

src/transitions-inl.h

Index: src/transitions-inl.h
diff --git a/src/transitions-inl.h b/src/transitions-inl.h
index 0de98541526ef4936525863ed03bf4aa7d34b3d7..09284cbddbf50b7728e917953c0cfbcaf1f66be6 100644
--- a/src/transitions-inl.h
+++ b/src/transitions-inl.h
@@ -161,8 +161,8 @@ void TransitionArray::SetTarget(int transition_number, Map* value) {
 PropertyDetails TransitionArray::GetTargetDetails(int transition_number) {
   Map* map = GetTarget(transition_number);
   DescriptorArray* descriptors = map->instance_descriptors();
-  int descriptor = descriptors->LastAdded();
-  ASSERT(descriptor != DescriptorArray::kNotFound);
+  int descriptor = map->LastAdded();
+  ASSERT(descriptor != Map::kNoneAdded);
   return descriptors->GetDetails(descriptor);
 }