Redirection type of a redirecting factory can be deferred

tests/language/regress_23408_lib.dart

Index: tests/language/regress_23408_lib.dart
diff --git a/tools/canary.dart b/tests/language/regress_23408_lib.dart
similarity index 68%
copy from tools/canary.dart
copy to tests/language/regress_23408_lib.dart
index cca1f90cd7be8eb2481a00a89bbc7ba7edaa6d4f..09e76f7c943125a077985635fb69777fdc97193b 100644
--- a/tools/canary.dart
+++ b/tests/language/regress_23408_lib.dart
@@ -2,10 +2,10 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// Script which exits with code 42.
+library regress_23408_lib;
 
-import 'dart:io';
+import "regress_23408_test.dart" as main;
 
-void main() {
-  exitCode = 42;
+class C extends main.C {
+  C();
 }