Update or delete language tests using obsolete interfaces or default factory

tests/language/interface_factory_constructor_negative_test.dart

Index: tests/language/interface_factory_constructor_negative_test.dart
===================================================================
--- tests/language/interface_factory_constructor_negative_test.dart	(revision 15648)
+++ tests/language/interface_factory_constructor_negative_test.dart	(working copy)
@@ -1,17 +0,0 @@
-// Copyright (c) 2011, 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.
-
-interface A {
-  factory A();
-}
-
-class InterfaceFactoryConstructorNegativeTest {
-
-  static testMain() {
-  }
-}
-
-main() {
-  InterfaceFactoryConstructorNegativeTest.testMain();
-}