Add tools/ddbg_service.

runtime/bin/vmservice/observatory/test/bad_web_socket_address_test.dart

+// 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.
+
+import "package:observatory/service_io.dart";
+import 'package:unittest/unittest.dart';
+
+void testBadWebSocket() {
+  var vm = new WebSocketVM(new WebSocketVMTarget('ws://karatekid/ws'));
+  vm.load().catchError(expectAsync((error) {
+        expect(error is ServiceException, isTrue);
+      }));
+}
+
+main() {
+  test('bad web socket address', testBadWebSocket);
+}
+