Make _FileSystemWatcher.watch private.

sdk/lib/io/file_system_entity.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.
 
 part of dart.io;
 
 /**
  * The type of an entity on the file system, such as a file, directory, or link.
  *
  * These constants are used by the [FileSystemEntity] class
@@ skipping 421 matching lines @@
    *   * The [FileSystemEntity] being watches, is deleted.
    *
    * Use `events` to specify what events to listen for. The constants in
    * [FileSystemEvent] can be or'ed together to mix events. Default is
    * [FileSystemEvent.ALL].
    *
    * A move event may be reported as seperate delete and create events.
    */
   Stream<FileSystemEvent> watch({int events: FileSystemEvent.ALL,
                                  bool recursive: false})
-     => _FileSystemWatcher.watch(_trimTrailingPathSeparators(path),
+     => _FileSystemWatcher._watch(_trimTrailingPathSeparators(path),
                                  events,
                                  recursive);
 
   Future<FileSystemEntity> _delete({bool recursive: false});
   void _deleteSync({bool recursive: false});
 
   /**
    * Checks whether two paths refer to the same object in the
    * file system. Returns a [:Future<bool>:] that completes with the result.
    *
@@ skipping 367 matching lines @@
     var buffer = new StringBuffer();
     buffer.write("FileSystemMoveEvent('$path'");
     if (destination != null) buffer.write(", '$destination'");
     buffer.write(')');
     return buffer.toString();
   }
 }
 
 
 class _FileSystemWatcher {
-  external static Stream<FileSystemEvent> watch(
+  external static Stream<FileSystemEvent> _watch(
       String path, int events, bool recursive);
   external static bool get isSupported;
 }