Check type bounds of redirecting factories (issue 14699).

tests/language/malbounded_redirecting_factory_test.dart

Index: tests/language/malbounded_redirecting_factory_test.dart
===================================================================
--- tests/language/malbounded_redirecting_factory_test.dart	(revision 0)
+++ tests/language/malbounded_redirecting_factory_test.dart	(revision 0)
@@ -0,0 +1,29 @@
+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// 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.
+
+import 'package:expect/expect.dart';
+
+class A<Ta
+           extends num  /// 02: continued
+                      > implements B<Ta>, C<Ta> { }
+
+class B<Tb
+           extends num  /// 03: continued
+                      > {
+  factory B() = A<Tb>;
+}
+
+class C<Tc
+           extends num  /// 04: continued
+                      > {
+  factory C() = B<Tc>;
+}
+
+main() {
+  new C<int>();
+  new C<String>();  /// 01: static type warning
+  new C<String>();  /// 02: static type warning, dynamic type error
+  new C<String>();  /// 03: static type warning, dynamic type error
+  new C<String>();  /// 04: static type warning, dynamic type error
+}