[turbofan] Store nodes use only MachineRepresentation, not MachineType.

test/cctest/compiler/test-changes-lowering.cc

Index: test/cctest/compiler/test-changes-lowering.cc
diff --git a/test/cctest/compiler/test-changes-lowering.cc b/test/cctest/compiler/test-changes-lowering.cc
index 965382cfd6a46d55a8f67d5ab9649100bd5aff3c..e850da7735d725160bbf6cf61b021e53229bf057 100644
--- a/test/cctest/compiler/test-changes-lowering.cc
+++ b/test/cctest/compiler/test-changes-lowering.cc
@@ -205,7 +205,7 @@ TEST(RunChangeTaggedToFloat64) {
 
   t.BuildStoreAndLower(t.simplified()->ChangeTaggedToFloat64(),
                        t.machine()->Store(StoreRepresentation(
-                           MachineType::Float64(), kNoWriteBarrier)),
+                           MachineRepresentation::kFloat64, kNoWriteBarrier)),
                        &result);
 
   {