Clean up the Windows watcher.

pkg/analysis_server/test/physical_resource_provider_test.dart

 // Copyright (c) 2014, 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.physical.resource.provider;
 
 import 'dart:async';
 import 'dart:io' as io;
 
 import 'package:analysis_server/src/resource.dart';
@@ skipping 14 matching lines @@
         tempPath = tempDirectory.absolute.path;
       });
 
       tearDown(() {
         tempDirectory.deleteSync(recursive: true);
       });
 
       group('Watch', () {
 
         Future delayed(computation()) {
+          // Give the tests 1 second to detect the changes. While it may only
+          // take up to a few hundred ms, a whole second gives a good margin
+          // for when running tests.
           return new Future.delayed(
               new Duration(seconds: 1), computation);
         }
 
         watchingFolder(String path, test(List<WatchEvent> changesReceived)) {
           // Delay before we start watching the folder.  This is necessary
           // because on MacOS, file modifications that occur just before we
           // start watching are sometimes misclassified as happening just after
           // we start watching.
           return delayed(() {
@@ skipping 168 matching lines @@
           expect(children[1], _isFolder);
           expect(children[2], _isFile);
         });
       });
     });
 }
 
 var _isFile = new isInstanceOf<File>();
 var _isFolder = new isInstanceOf<Folder>();
 var _isMemoryResourceException = new isInstanceOf<MemoryResourceException>();