Cleanup change.

runtime/vm/aot_optimizer.cc

Index: runtime/vm/aot_optimizer.cc
diff --git a/runtime/vm/aot_optimizer.cc b/runtime/vm/aot_optimizer.cc
index 7f10d520560e9f90c4b26f150deb420101fe7a94..5dfe8f507c5c258647c1c4d08ef7533b7a01ab75 100644
--- a/runtime/vm/aot_optimizer.cc
+++ b/runtime/vm/aot_optimizer.cc
@@ -1407,8 +1407,8 @@ static bool TryExpandTestCidsResult(ZoneGrowableArray<intptr_t>* results,
     const Class& cls = Class::Handle(class_table.At(kSmiCid));
     const Class& type_class = Class::Handle(type.type_class());
     const bool smi_is_subtype =
-        cls.IsSubtypeOf(TypeArguments::Handle(), type_class,
-                        TypeArguments::Handle(), NULL, NULL, Heap::kOld);
+        cls.IsSubtypeOf(Object::null_type_arguments(), type_class,
+                        Object::null_type_arguments(), NULL, NULL, Heap::kOld);
     results->Add((*results)[results->length() - 2]);
     results->Add((*results)[results->length() - 2]);
     for (intptr_t i = results->length() - 3; i > 1; --i) {