Fix newly added regression test that left processes hanging on Windows.

tests/standalone/io/regress_7191_script.dart

 // Copyright (c) 2012, 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:io';
 import 'dart:isolate';
 
 main() {
   // Open a port to make the script hang.
   var port = new ReceivePort();
   // Start sub-process when receiving data.
   stdin.onData = () {
     var data = stdin.read();

[Søren Gjesse, 2012/12/11 09:57:44]

Check that data is [0] here as well?

     var options = new Options();
     Process.start(options.executable, [options.script]).then((p) {
       p.stdout.onData = p.stdout.read;
       p.stderr.onData = p.stderr.read;
       // When receiving data again, kill sub-process and exit.
       stdin.onData = () {
         var data = stdin.read();
-        Expect.listEquals([1], data);
+        Expect.listEquals([0], data);
         p.kill();
-        p.onExit = port.close;
+        p.onExit = exit;
       };
       // Close stdout. If handles are incorrectly inherited this will
       // not actually close stdout and the test will hang.
       stdout.close();
     });
   };
-}
+}