Allow more time for tests on Windows. (#2193)

Author: davidmorgan

pkgs/watcher/test/directory_watcher/polling_test.dart

@@ -2,6 +2,9 @@
 // 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.
 
+@Timeout.factor(2)
+library;
+
 import 'package:test/test.dart';
 import 'package:watcher/watcher.dart';
 

pkgs/watcher/test/directory_watcher/windows_test.dart

@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @TestOn('windows')
+@Timeout.factor(2)
 library;
 
 import 'dart:async';