Use the new test runner.

test/shelf_proxy_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 'dart:async';
 
 import 'package:http/http.dart' as http;
 import 'package:http/testing.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 import 'package:shelf/shelf.dart' as shelf;
@@ skipping 197 matching lines @@
           containsPair('warning', '214 shelf_proxy "GZIP decoded"'));
     }), completes);
   });
 }
 
 /// Creates a proxy server proxying to a server running [handler].
 ///
 /// [targetPath] is the root-relative path on the target server to proxy to. It
 /// defaults to `/`.
 void createProxy(shelf.Handler handler, {String targetPath}) {
-  handler = wrapAsync(handler, 'target server handler');
+  handler = expectAsync(handler, reason: 'target server handler');
   schedule(() {
     return shelf_io.serve(handler, 'localhost', 0).then((targetServer) {
       targetUri = Uri.parse('http://localhost:${targetServer.port}');
       if (targetPath != null) targetUri = targetUri.resolve(targetPath);
-      var proxyServerHandler = wrapAsync(
-          proxyHandler(targetUri), 'proxy server handler');
+      var proxyServerHandler = expectAsync(
+          proxyHandler(targetUri), reason: 'proxy server handler');
 
       return shelf_io.serve(proxyServerHandler, 'localhost', 0)
           .then((proxyServer) {
         proxyUri = Uri.parse('http://localhost:${proxyServer.port}');
 
         currentSchedule.onComplete.schedule(() {
           proxyServer.close(force: true);
           targetServer.close(force: true);
         }, 'tear down servers');
       });
@@ skipping 13 matching lines @@
 /// Schedules a GET request with [headers] to the proxy server.
 Future<http.Response> get({Map<String, String> headers}) {
   return schedule(() {
     var uri = proxyUri;
     var request = new http.Request('GET', uri);
     if (headers != null) request.headers.addAll(headers);
     request.followRedirects = false;
     return request.send().then(http.Response.fromStream);
   }, 'GET proxy server');
 }