Rewrite regress_7191 to avoid changing stream subscription.

tests/standalone/io/regress_7191_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.
 
 // Regression test for http://dartbug.com/7191.
 
 // Starts a sub-process which in turn starts another sub-process and then closes
 // its standard output. If handles are incorrectly inherited on Windows, this
 // will lead to a situation where the stdout of the first sub-process is never
 // closed which will make this test hang.
 
 import 'dart:io';
 import 'dart:isolate';
 
 main() {
   var port = new ReceivePort();
   var options = new Options();
   var executable = options.executable;
   var scriptDir = new Path(options.script).directoryPath;
   var script = scriptDir.append('regress_7191_script.dart').toNativePath();
   Process.start(executable, [script]).then((process) {
     process.stdin.writeBytes([0]);
-      process.stdout.listen((_) { },
-                            onDone: () { process.stdin.writeBytes([0]); });
+    process.stdout.listen((_) { },
+                           onDone: () { process.stdin.writeBytes([0]); });
     process.stderr.listen((_) { });
     process.exitCode.then((exitCode) => port.close());

[Mads Ager (google), 2013/04/10 06:10:38]

We should add verification of the exitCode here. That would have caught this
issue because the exit code of the script was non-zero.

Anders, could you add that?

[Anders Johnsen, 2013/04/10 11:41:32]

Yep, done in https://codereview.chromium.org/13851008.

   });
 }