[turbofan] JSTypedLowering can just look at the type hints.

test/unittests/compiler/js-typed-lowering-unittest.cc

Index: test/unittests/compiler/js-typed-lowering-unittest.cc
diff --git a/test/unittests/compiler/js-typed-lowering-unittest.cc b/test/unittests/compiler/js-typed-lowering-unittest.cc
index 5128a3faba27fc4d1219eed9b02a58c77db8ed65..1ed438117a1730b7dc4836ddaf9fbaf0f73129f8 100644
--- a/test/unittests/compiler/js-typed-lowering-unittest.cc
+++ b/test/unittests/compiler/js-typed-lowering-unittest.cc
@@ -87,9 +87,8 @@ class JSTypedLoweringTest : public TypedGraphTest {
     // TODO(titzer): mock the GraphReducer here for better unit testing.
     GraphReducer graph_reducer(zone(), graph());
     JSTypedLowering reducer(&graph_reducer, &deps_,
-                            JSTypedLowering::kDeoptimizationEnabled |
-                                JSTypedLowering::kTypeFeedbackEnabled,
-                            &jsgraph, zone());
+                            JSTypedLowering::kDeoptimizationEnabled, &jsgraph,
+                            zone());
     return reducer.Reduce(node);
   }