Upgrade to the new test runner.

test/web_socket_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.
 
 library shelf_web_socket.web_socket_test;
 
 import 'dart:io';
 
 import 'package:http/http.dart' as http;
 import 'package:shelf/shelf_io.dart' as shelf_io;
 import 'package:shelf_web_socket/shelf_web_socket.dart';
-import 'package:unittest/unittest.dart';
+import 'package:test/test.dart';
 
 Map<String, String> get _handshakeHeaders => {
   "Upgrade": "websocket",
   "Connection": "Upgrade",
   "Sec-WebSocket-Key": "x3JJHMbDL1EzLkh9GBhXDw==",
   "Sec-WebSocket-Version": "13"
 };
 
 void main() {
   test("can communicate with a dart:io WebSocket client", () {
@@ skipping 149 matching lines @@
     expect(() => webSocketHandler((_) => null, protocols: ['foo']),
         throwsArgumentError);
   });
 }
 
 Matcher hasStatus(int status) => completion(predicate((response) {
   expect(response, new isInstanceOf<http.Response>());
   expect(response.statusCode, equals(status));
   return true;
 }));