Revert "Migrating a block of dart 2:"

tests/language_2/class_keyword_test.dart

Index: tests/language_2/class_keyword_test.dart
diff --git a/tests/language_2/class_keyword_test.dart b/tests/language_2/class_keyword_test.dart
deleted file mode 100644
index fc296ed3bac8383f592369c4e872a32b09defc26..0000000000000000000000000000000000000000
--- a/tests/language_2/class_keyword_test.dart
+++ /dev/null
@@ -1,12 +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.
-
-// Test that "class" cannot be used as identifier.
-
-class foo {}
-
-void main() {
-  int class = 10; //# 01: compile-time error
-  print("$class"); //# 02: compile-time error
-}