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

src/code-factory.h

Index: src/code-factory.h
diff --git a/src/code-factory.h b/src/code-factory.h
index 1b2cc56b7e694311b007b11f213f214fde4c72bd..7e96a7f395336fbe1556039cae4baa2f5ccb517f 100644
--- a/src/code-factory.h
+++ b/src/code-factory.h
@@ -39,6 +39,7 @@ class CodeFactory final {
                                               TypeofMode typeof_mode);
   static Callable KeyedLoadIC(Isolate* isolate);
   static Callable KeyedLoadICInOptimizedCode(Isolate* isolate);
+  static Callable KeyedLoadIC_Megamorphic(Isolate* isolate);
   static Callable CallIC(Isolate* isolate, int argc,
                          ConvertReceiverMode mode = ConvertReceiverMode::kAny,
                          TailCallMode tail_call_mode = TailCallMode::kDisallow);