Encapsulate compare nil ic_state.

src/type-info.cc

Index: src/type-info.cc
diff --git a/src/type-info.cc b/src/type-info.cc
index b256bb406e4de7f8c40931b856d4b5ec46919bb1..d8eebfb69724ff37ab7ce3cb4b2bf1cfad7f4777 100644
--- a/src/type-info.cc
+++ b/src/type-info.cc
@@ -377,12 +377,9 @@ void TypeFeedbackOracle::CompareType(TypeFeedbackId id,
     CompareIC::StubInfoToType(
         stub_minor_key, left_type, right_type, combined_type, map, isolate());
   } else if (code->is_compare_nil_ic_stub()) {
-    CompareNilICStub::State state(code->compare_nil_state());
-    *combined_type = CompareNilICStub::StateToType(isolate_, state, map);
-    Handle<Type> nil_type = handle(code->compare_nil_value() == kNullValue
-        ? Type::Null() : Type::Undefined(), isolate_);
-    *left_type = *right_type =
-        handle(Type::Union(*combined_type, nil_type), isolate_);
+    CompareNilICStub stub(code->extended_extra_ic_state());
+    *combined_type = stub.GetType(isolate_, map);
+    *left_type = *right_type = stub.GetInputType(isolate_, map);
   }
 }