Provisionally stop working around issues 9252 and 9253.

pkg/scheduled_test/test/utils.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.
 
 library test_utils;
 
 import 'dart:io';
 import 'dart:async';
 
 import '../lib/src/utils.dart';
@@ skipping 27 matching lines @@
 }
 
 /// Returns a [Future] that will complete in [milliseconds].
 Future sleep(int milliseconds) {
   var completer = new Completer();
   mock_clock.newTimer(new Duration(milliseconds: milliseconds), () {
     completer.complete();
   });
   return completer.future;
 }
-
-// TODO(nweiz): Remove this when issue 9252 is fixed.
-/// Asynchronously recursively deletes [dir]. Returns a [Future] that completes
-/// when the deletion is done.
-Future deleteDir(String dir) =>
-  _attemptRetryable(() => new Directory(dir).delete(recursive: true));
-
-/// On Windows, we sometimes get failures where the directory is still in use
-/// when we try to do something with it. This is usually because the OS hasn't
-/// noticed yet that a process using that directory has closed. To be a bit
-/// more resilient, we wait and retry a few times.
-///
-/// Takes a [callback] which returns a future for the operation being attempted.
-/// If that future completes with an error, it will slepp and then [callback]
-/// will be invoked again to retry the operation. It will try a few times before
-/// giving up.
-Future _attemptRetryable(Future callback()) {
-  // Only do lame retry logic on Windows.
-  if (Platform.operatingSystem != 'windows') return callback();
-
-  var attempts = 0;
-  makeAttempt(_) {
-    attempts++;
-    return callback().catchError((e) {
-      if (attempts >= 10) {
-        throw 'Could not complete operation. Gave up after $attempts attempts.';
-      }
-
-      return sleep(500).then(makeAttempt);
-    });
-  }
-
-  return makeAttempt(null);
-}