Migrate block 163 to Dart 2.0.

tests/language/unsigned_right_shift_test.dart

Index: tests/language/unsigned_right_shift_test.dart
diff --git a/tests/language/unsigned_right_shift_test.dart b/tests/language/unsigned_right_shift_test.dart
deleted file mode 100644
index e35fa5d093a28dc4cd9c8a7cef4b3d0affc5af57..0000000000000000000000000000000000000000
--- a/tests/language/unsigned_right_shift_test.dart
+++ /dev/null
@@ -1,12 +0,0 @@
-// 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.
-
-// The >>> operator is not supported in Dart
-
-main() {
-  var foo = -10
-    >>> 1 //# 01: compile-time error
-      ;
-  foo >>>= 1; //# 02: compile-time error
-}