[turbofan] Remove phase ordering problem in JSToNumber lowering.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 3973797aa144c8703f562db7c32f253df297a43d..f0325289067960fc44d08344e74e9d75b5532dfa 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -1845,6 +1845,11 @@ Type* ChangeRepresentation(Type* type, Type* rep, Zone* zone) {
 
 }  // namespace
 
+Type* Typer::Visitor::TypeChangeTaggedSignedToWord32(Node* node) {
+  Type* arg = Operand(node, 0);
+  // TODO(neis): DCHECK(arg->Is(Type::Signed32()));
+  return ChangeRepresentation(arg, Type::UntaggedIntegral32(), zone());
+}
 
 Type* Typer::Visitor::TypeChangeTaggedToInt32(Node* node) {
   Type* arg = Operand(node, 0);