Merge IO v2 branch to bleeding edge

tests/standalone/io/regress_7191_script.dart

-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// 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 '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();
+  var subscription;
+  subscription = stdin.listen((data) {
     var options = new Options();
     Process.start(options.executable, [options.script]).then((p) {
-      p.stdout.onData = p.stdout.read;
-      p.stderr.onData = p.stderr.read;
+      p.stdout.listen((_) { });
+      p.stderr.listen((_) { });
       // When receiving data again, kill sub-process and exit.
-      stdin.onData = () {
-        var data = stdin.read();
+      subscription.onData((data) {
         Expect.listEquals([0], data);
         p.kill();
-        p.onExit = exit;
-      };
+        p.exitCode.then(exit);
+      });
       // Close stdout. If handles are incorrectly inherited this will
       // not actually close stdout and the test will hang.
       stdout.close();
     });
-  };
+  });
 }