Clean up isolate tests.

tests/isolate/unresolved_ports_negative_test.dart

Index: tests/isolate/unresolved_ports_negative_test.dart
diff --git a/tests/isolate/unresolved_ports_negative_test.dart b/tests/isolate/unresolved_ports_negative_test.dart
deleted file mode 100644
index 30076459bcf4f8806b5aec4cc3580423ee240fbf..0000000000000000000000000000000000000000
--- a/tests/isolate/unresolved_ports_negative_test.dart
+++ /dev/null
@@ -1,13 +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.
-
-// negative test to ensure that unresolved_ports works.
-library unresolved_ports_negative;
-import 'dart:isolate';
-import '../../pkg/unittest/lib/unittest.dart';
-import 'unresolved_ports_test.dart' as positive_test;
-
-main() {
-  positive_test.baseTest(failForNegativeTest: true);
-}