Update or delete language tests using obsolete interfaces or default factory

tests/language/default_factory3_test.dart

Index: tests/language/default_factory3_test.dart
===================================================================
--- tests/language/default_factory3_test.dart	(revision 15648)
+++ tests/language/default_factory3_test.dart	(working copy)
@@ -1,12 +1,12 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2012, 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.
 
 // Check possibly still unresolved upper bounds of default factory class.
 
 
-interface A<T extends Foo> default _AImpl<T extends Foo> {
-  const A();
+abstract class A<T extends Foo> {
+  factory A() = _AImpl<T>;
 }
 
 class Moo extends Foo {}