Update dart:io tests to use asyncStart/asyncEnd

tests/standalone/io/regress_10026_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:convert';
 import 'dart:io';
-import 'dart:isolate';
+
+import "package:async_helper/async_helper.dart";
+import "package:expect/expect.dart";
 
 void testZLibInflate_regress10026() {
   test(data, expect) {
-    var port = new ReceivePort();
+    asyncStart();
     var controller = new StreamController(sync: true);
     controller.stream
         .transform(ZLIB.decoder)
         .transform(UTF8.decoder)
         .fold(new StringBuffer(), (buffer, s) {
           buffer.write(s);
           return buffer;
         })
         .then((out) {
           Expect.equals(out.toString(), expect);
-          port.close();
+          asyncEnd();
         });
     controller.add(data);
     controller.close();
   }
   // Generated by using 'gzip -c | od -v -tu1 -An -w12' and adding commas.
   test([
      31, 139,   8,   8, 238,  42, 167,  81,   0,   3, 116, 101,
     120, 116,  46, 116, 120, 116,   0, 125,  84,  79, 175, 147,
      64,  16,  63, 183, 159,  98, 196, 139,  38, 165, 244, 249,
     212,  52,  20, 136,  70,  77, 188, 168,   7, 189, 120, 156,
@@ skipping 96 matching lines @@
 </div>
 </body>
 </html>
 ''');
 }
 
 void main() {
   testZLibInflate_regress10026();
 }