Update or delete language tests using obsolete interfaces or default factory

tests/language/dynamic_test.dart

Index: tests/language/dynamic_test.dart
===================================================================
--- tests/language/dynamic_test.dart	(revision 15648)
+++ tests/language/dynamic_test.dart	(working copy)
@@ -1,11 +1,11 @@
-// 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.
 //
 // Dart test program testing the use of 'dynamic' in generic types.
 // @static-clean
 
-interface Iface<K,V> {
+abstract class Iface<K,V> {
 }
 
 class M1<K, V> implements Iface<K, V> {