- Fix outdated use of factory clause.

bin/file.dart

 // Copyright (c) 2011, 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.
 
-interface File factory _File {
+interface File default _File {
   /**
    * Create a File object.
    */
   File(String name);
 
   /**
    * Check if the file exists. The [existsHandler] is called with the
    * result when the operation completes.
    */
   void exists();
@@ skipping 245 matching lines @@
 
 interface FileOutputStream extends OutputStream {
 }
 
 
 class FileIOException implements Exception {
   const FileIOException([String this.message = ""]);
   String toString() => "FileIOException: $message";
   final String message;
 }