Migrated test block 19 to Dart 2.0.

tests/corelib/reg_exp_pattern_test.dart

Index: tests/corelib/reg_exp_pattern_test.dart
diff --git a/tests/corelib/reg_exp_pattern_test.dart b/tests/corelib/reg_exp_pattern_test.dart
deleted file mode 100644
index 7b4d66620674a86293f81ef329df1bbaca30e87a..0000000000000000000000000000000000000000
--- a/tests/corelib/reg_exp_pattern_test.dart
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright (c) 2014, 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 for testing regular expressions in Dart.
-
-import "package:expect/expect.dart";
-
-// Regression test for http://dartbug.com/17998
-
-main() {
-  for (var s in [
-    r"a",
-    r"a|b",
-    r"(?:)",
-    r"^",
-    r"$",
-    r"^$",
-    r"$^",
-    r"",
-    r"\\",
-    r"/",
-    r"[^]",
-    "\x00",
-  ]) {
-    Expect.equals(s, new RegExp(s).pattern);
-  }
-}