Remove the Path class from dart:io

sdk/lib/io/file_impl.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;
 
 // Read the file in blocks of size 64k.
 const int _BLOCK_SIZE = 64 * 1024;
 
 
@@ skipping 228 matching lines @@
   SendPort _fileService;
 
   // Constructor for file.
   _File(String this.path) {
     if (path is! String) {
       throw new ArgumentError('${Error.safeToString(path)} '
                               'is not a String');
     }
   }
 
-  // Constructor from Path for file.
-  _File.fromPath(Path path) : this(path.toNativePath());
-
   Future<bool> exists() {
     _ensureFileService();
     List request = new List(2);
     request[0] = _EXISTS_REQUEST;
     request[1] = path;
     return _fileService.call(request).then((response) {
       if (_isErrorResponse(response)) {
         throw _exceptionFromResponse(response, "Cannot check existence", path);
       }
       return response;
@@ skipping 77 matching lines @@
 
   external static _renameLink(String oldPath, String newPath);
 
   File renameSync(String newPath) {
     var result = _rename(path, newPath);
     throwIfError(result, "Cannot rename file to '$newPath'", path);
     return new File(newPath);
   }
 
   Directory get directory {
-    Path path = new Path(this.path).directoryPath;
-    return new Directory.fromPath(path);
+    _Path path = new _Path(this.path).directoryPath;
+    return new Directory(path.toNativePath());
   }
 
   Future<RandomAccessFile> open({FileMode mode: FileMode.READ}) {
     _ensureFileService();
     if (mode != FileMode.READ &&
         mode != FileMode.WRITE &&
         mode != FileMode.APPEND) {
       return new Future.error(new ArgumentError());
     }
     List request = new List(3);
@@ skipping 619 matching lines @@
   void _checkNotClosed() {
     if (closed) {
       throw new FileException("File closed", path);
     }
   }
 
   Future _closedException() {
     return new Future.error(new FileException("File closed", path));
   }
 }