Work around issue 9252 in scheduled_test.

utils/pub/io.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.
 
 /// Helper functionality to make working with IO easier.
 library io;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:isolate';
@@ skipping 110 matching lines @@
 /// Creates a temp directory whose name will be based on [dir] with a unique
 /// suffix appended to it. If [dir] is not provided, a temp directory will be
 /// created in a platform-dependent temporary location. Returns the path of the
 /// created directory.
 String createTempDir([dir = '']) {
   var tempDir = new Directory(dir).createTempSync();
   log.io("Created temp directory ${tempDir.path}");
   return tempDir.path;
 }
 
+// TODO(nweiz): Remove this when issue 9252 is fixed.
 /// Asynchronously recursively deletes [dir]. Returns a [Future] that completes
 /// when the deletion is done.
 Future<String> deleteDir(String dir) {
   return _attemptRetryable(() => log.ioAsync("delete directory $dir",
       new Directory(dir).delete(recursive: true).then((_) => dir)));
 }
 
 /// Asynchronously lists the contents of [dir]. If [recursive] is `true`, lists
 /// subdirectory contents (defaults to `false`). If [includeHiddenFiles] is
 /// `true`, includes files and directories beginning with `.` (defaults to
@@ skipping 79 matching lines @@
       // If there is a non-directory there (file or symlink), delete it.
       deleteFile(dir);
       return createDir(dir);
     }
 
     // Just create it.
     return createDir(dir);
   });
 }
 
+// TODO(nweiz): remove this when issue 9253 is fixed.
 /// Renames (i.e. moves) the directory [from] to [to]. Returns a [Future] with
 /// the destination directory.
 Future<String> renameDir(String from, String to) {
   log.io("Renaming directory $from to $to.");
 
   return _attemptRetryable(() => new Directory(from).rename(to)).then((dir) {
     log.fine("Renamed directory $from to $to.");
     return to;
   });
 }
@@ skipping 570 matching lines @@
   const PubProcessResult(this.stdout, this.stderr, this.exitCode);
 
   bool get success => exitCode == 0;
 }
 
 /// Gets a [Uri] for [uri], which can either already be one, or be a [String].
 Uri _getUri(uri) {
   if (uri is Uri) return uri;
   return Uri.parse(uri);
 }