Revert r20952, r20953, r20954

tests/standalone/io/sleep_test.dart

Index: tests/standalone/io/sleep_test.dart
diff --git a/tests/standalone/io/sleep_test.dart b/tests/standalone/io/sleep_test.dart
deleted file mode 100644
index d953bf9f1a29536b9cc5652ebbb4380f91448304..0000000000000000000000000000000000000000
--- a/tests/standalone/io/sleep_test.dart
+++ /dev/null
@@ -1,19 +0,0 @@
-// 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";
-
-test(int milliseconds) {
-  var watch = new Stopwatch();
-  watch.start();
-  sleep(new Duration(milliseconds: milliseconds));
-  watch.stop();
-  Expect.isTrue(watch.elapsedMilliseconds + 1 >= milliseconds);
-}
-
-main() {
-  test(1);
-  test(10);
-  test(100);
-}