Migrate test block 47 and downstream dependencies to Dart 2.0.

tests/language_strong/class_cycle2_test.dart

Index: tests/language_strong/class_cycle2_test.dart
diff --git a/tests/language_strong/class_cycle2_test.dart b/tests/language_strong/class_cycle2_test.dart
deleted file mode 100644
index 2b1bb6576eaf322e4605287fe3c9f3163f1b9519..0000000000000000000000000000000000000000
--- a/tests/language_strong/class_cycle2_test.dart
+++ /dev/null
@@ -1,18 +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.
-// Check fail because of cycles in super class relationship.
-
-class C extends B {}
-
-class A extends B {}
-
-class B
-  extends A // //# 01: compile-time error
-  extends A // //# 02: compile-time error
-{}
-
-main() {
-  new C(); // //# 01: continued
-  new List<C>(); // //# 02: continued
-}