Use handle lists in Map::FindTransitionedMap.

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 0b843bd45b32eb6d57c1efa86ee784c59290c817..d758895c37b1fef3e4afc3570f1454b72780c102 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -4095,21 +4095,21 @@ HValue* HGraphBuilder::HandlePolymorphicElementAccess(HValue* object,
   }
 
   // Elements_kind transition support.
-  MapList transition_target(maps->length());
+  MapHandleList transition_target(maps->length());
   // Collect possible transition targets.
-  MapList possible_transitioned_maps(maps->length());
+  MapHandleList possible_transitioned_maps(maps->length());
   for (int i = 0; i < maps->length(); ++i) {
     Handle<Map> map = maps->at(i);
     ElementsKind elements_kind = map->elements_kind();
     if (elements_kind == FAST_DOUBLE_ELEMENTS ||
         elements_kind == FAST_ELEMENTS) {
-      possible_transitioned_maps.Add(*map);
+      possible_transitioned_maps.Add(map);
     }
   }
   // Get transition target for each map (NULL == no transition).
   for (int i = 0; i < maps->length(); ++i) {
     Handle<Map> map = maps->at(i);
-    Map* transitioned_map =
+    Handle<Map> transitioned_map =
         map->FindTransitionedMap(&possible_transitioned_maps);
     transition_target.Add(transitioned_map);
   }
@@ -4119,9 +4119,9 @@ HValue* HGraphBuilder::HandlePolymorphicElementAccess(HValue* object,
   for (int i = 0; i < maps->length(); ++i) {
     Handle<Map> map = maps->at(i);
     ASSERT(map->IsMap());
-    if (transition_target.at(i) != NULL) {
+    if (!transition_target.at(i).is_null()) {
       object = AddInstruction(new(zone()) HTransitionElementsKind(
-          object, map, Handle<Map>(transition_target.at(i))));
+          object, map, transition_target.at(i)));
     } else {
       type_todo[map->elements_kind()] = true;
       if (map->elements_kind() >= FIRST_EXTERNAL_ARRAY_ELEMENTS_KIND) {