Update the test runner to use the new dart:io API

tests/standalone/io/test_runner_test.dart

Index: tests/standalone/io/test_runner_test.dart
diff --git a/tests/standalone/io/test_runner_test.dart b/tests/standalone/io/test_runner_test.dart
index 41d9727400c07c233367ea8926a2a6bf8560243e..9c43a9ced2dc203d4d9ec96afb2d519e1bde65ef 100644
--- a/tests/standalone/io/test_runner_test.dart
+++ b/tests/standalone/io/test_runner_test.dart
@@ -1,4 +1,4 @@
-// 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.
 
@@ -72,8 +72,8 @@ class CustomTestSuite extends TestSuite {
     var crashCommand = new Command(getProcessTestFileName(),
                                    ["0", "0", "1", "1"]);
     // The crash test sometimes times out. Run it with a large timeout
-    // to help diagnose the delay. 
-    // The test loads a new executable, which may sometimes take a long time. 
+    // to help diagnose the delay.
+    // The test loads a new executable, which may sometimes take a long time.
     // It involves a wait on the VM event loop, and possible system
     // delays.
     return _makeTestCase(name, LONG_TIMEOUT, crashCommand, expectations);
@@ -94,7 +94,7 @@ void testProcessQueue() {
   var maxProcesses = 2;
   var maxBrowserProcesses = maxProcesses;
   new ProcessQueue(maxProcesses, maxBrowserProcesses,
-      new Date.now(), [new CustomTestSuite()], [], TestController.finished);
+      new DateTime.now(), [new CustomTestSuite()], [], TestController.finished);
 }
 
 void main() {