dart:io | Tiny change to Link.exists().

sdk/lib/io/link.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;
 
 /**
  * [Link] objects are references to filesystem links.
  *
  */
@@ skipping 110 matching lines @@
   final String path;
 
   SendPort _fileService;
 
   _Link(String this.path);
 
   _Link.fromPath(Path inputPath) : path = inputPath.toNativePath();
 
   String toString() => "Link: '$path'";
 
-  Future<bool> exists() {
-    // TODO(whesse): Replace with asynchronous version.
-    return new Future.value(existsSync());
-  }
+  Future<bool> exists() => FileSystemEntity.isLink(path);
 
   bool existsSync() => FileSystemEntity.isLinkSync(path);
 
   Future<Link> create(String target) {
     _ensureFileService();
     if (Platform.operatingSystem == 'windows') {
       target = _makeWindowsLinkTarget(target);
     }
     List request = new List(3);
     request[0] = _CREATE_LINK_REQUEST;
@@ skipping 130 matching lines @@
       if (path != null) {
         sb.write(", path = $path");
       }
     }
     return sb.toString();
   }
   final String message;
   final String path;
   final OSError osError;
 }