[KeyedLoadIC] Support Smi "handlers" for simple field loads

src/type-feedback-vector.h

Index: src/type-feedback-vector.h
diff --git a/src/type-feedback-vector.h b/src/type-feedback-vector.h
index cfcb6dbd699be22a2fd8d52d18668f7a6a508ff9..5355ee71884a1096c0c185f0b5c4ac097684d2e3 100644
--- a/src/type-feedback-vector.h
+++ b/src/type-feedback-vector.h
@@ -557,7 +557,7 @@ class KeyedLoadICNexus : public FeedbackNexus {
 
   // name can be a null handle for element loads.
   void ConfigureMonomorphic(Handle<Name> name, Handle<Map> receiver_map,
-                            Handle<Code> handler);
+                            Handle<Object> handler);
   // name can be null.
   void ConfigurePolymorphic(Handle<Name> name, MapHandleList* maps,
                             List<Handle<Object>>* handlers);