[turbofan] Correctify representation changes to bit.

src/compiler/js-graph.cc

Index: src/compiler/js-graph.cc
diff --git a/src/compiler/js-graph.cc b/src/compiler/js-graph.cc
index 7759ba14418c29c26aaa165d470958ba1abc0f93..c8f6062f3c901fd1042b7c0846f1d8aafa3fd005 100644
--- a/src/compiler/js-graph.cc
+++ b/src/compiler/js-graph.cc
@@ -200,6 +200,15 @@ Node* JSGraph::ExternalConstant(ExternalReference reference) {
 }
 
 
+Type* JSGraph::ZeroOneRangeType() {
+  if (!zero_one_range_type_.is_set()) {
+    zero_one_range_type_.set(
+        Type::Range(factory()->NewNumber(0), factory()->NewNumber(1), zone()));
+  }
+  return zero_one_range_type_.get();
+}
+
+
 void JSGraph::GetCachedNodes(NodeVector* nodes) {
   cache_.GetCachedNodes(nodes);
   SetOncePointer<Node>* ptrs[] = {