[runtime] Force internalize names used before lookup in in DescriptorArray and TransitionArray

src/transitions.cc

Index: src/transitions.cc
diff --git a/src/transitions.cc b/src/transitions.cc
index fc24b288677f62d78dab2aed40786ed4c001e62e..e63769e4af9640f1330e87fe4e701bf153a15d36 100644
--- a/src/transitions.cc
+++ b/src/transitions.cc
@@ -159,20 +159,21 @@ void TransitionArray::Insert(Handle<Map> map, Handle<Name> name,
 // static
 Map* TransitionArray::SearchTransition(Map* map, PropertyKind kind, Name* name,
                                        PropertyAttributes attributes) {
+  DCHECK(name->IsUniqueName());
   Object* raw_transitions = map->raw_transitions();
   if (IsSimpleTransition(raw_transitions)) {
     Map* target = GetSimpleTransition(raw_transitions);
     Name* key = GetSimpleTransitionKey(target);
-    if (!key->Equals(name)) return NULL;
+    if (key != name) return nullptr;
     PropertyDetails details = GetSimpleTargetDetails(target);
-    if (details.attributes() != attributes) return NULL;
-    if (details.kind() != kind) return NULL;
+    if (details.attributes() != attributes) return nullptr;
+    if (details.kind() != kind) return nullptr;
     return target;
   }
   if (IsFullTransitionArray(raw_transitions)) {
     TransitionArray* transitions = TransitionArray::cast(raw_transitions);
     int transition = transitions->Search(kind, name, attributes);
-    if (transition == kNotFound) return NULL;
+    if (transition == kNotFound) return nullptr;
     return transitions->GetTarget(transition);
   }
   return NULL;
@@ -195,6 +196,7 @@ Map* TransitionArray::SearchSpecial(Map* map, Symbol* name) {
 // static
 Handle<Map> TransitionArray::FindTransitionToField(Handle<Map> map,
                                                    Handle<Name> name) {
+  DCHECK(name->IsUniqueName());
   DisallowHeapAllocation no_gc;
   Map* target = SearchTransition(*map, kData, *name, NONE);
   if (target == NULL) return Handle<Map>::null();
@@ -545,9 +547,7 @@ int TransitionArray::Search(PropertyKind kind, Name* name,
                             PropertyAttributes attributes,
                             int* out_insertion_index) {
   int transition = SearchName(name, out_insertion_index);
-  if (transition == kNotFound) {
-    return kNotFound;
-  }
+  if (transition == kNotFound) return kNotFound;
   return SearchDetails(transition, kind, attributes, out_insertion_index);
 }
 }  // namespace internal