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

tests/standalone/io/test_runner_test.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:isolate";
 import "dart:async";
 import "dart:utf";
 import "../../../tools/testing/dart/test_runner.dart";
 import "../../../tools/testing/dart/test_suite.dart";
 import "../../../tools/testing/dart/status_file_parser.dart";
 import "../../../tools/testing/dart/test_options.dart";
@@ skipping 53 matching lines @@
   TestCase _makeNormalTestCase(name, expectations) {
     var command = new Command(new Options().executable,
                               [new Options().script, name]);
     return _makeTestCase(name, DEFAULT_TIMEOUT, command, expectations);
   }
 
   _makeCrashTestCase(name, expectations) {
     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);
   }
 
   _makeTestCase(name, timeout, command, expectations) {
     var configuration = new TestOptionsParser()
         .parse(['--timeout', '$timeout'])[0];
     return new TestCase(name,
                         [command],
                         configuration,
                         TestController.processCompletedTest,
                         new Set<String>.from(expectations));
   }
 }
 
 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() {
   // Run the test_runner_test if there are no command-line options.
   // Otherwise, run one of the component tests that always pass,
   // fail, or timeout.
   var arguments = new Options().arguments;
   if (arguments.isEmpty) {
     testProcessQueue();
   } else {
     switch (arguments[0]) {
       case 'pass':
         return;
       case 'fail-unexpected':
       case 'fail':
         Expect.fail("This test always fails, to test the test scripts.");
         break;
       case 'timeout':
         // Run for 10 seconds, then exit.  This tests a 2 second timeout.
         new Timer(new Duration(seconds: 10), (){ });
         break;
       default:
         throw "Unknown option ${arguments[0]} passed to test_runner_test";
     }
   }
 }