Remove deprecated parts of dart:async.

tests/standalone/io/http_cookie_test.dart

 // Copyright (c) 2013, 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:expect/expect.dart";
 import "dart:async";
 import "dart:io";
 
 void testCookies() {
   var cookies = [{'abc': 'def'},
@@ skipping 33 matching lines @@
             Expect.mapEquals(cookies[i], cookiesMap);
             response.listen(
                 (d) {},
                 onDone: () {
                   if (++count == cookies.length) {
                     client.close();
                     server.close();
                   }
                 });
           })
-          .catchError((e) {
+          .catchError((e, trace) {
             String msg = "Unexpected error $e";
-            var trace = getAttachedStackTrace(e);
             if (trace != null) msg += "\nStackTrace: $trace";
             Expect.fail(msg);
          });
     }
   });
 }
 
 void main() {
   testCookies();
 }