Make File.readSync return only the bytes read

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;
 
 
 class _FileStream extends Stream<List<int>> {
   // Stream controller.
   StreamController<List<int>> _controller;
@@ skipping 1038 matching lines @@
           new FileIOException("File closed '$_name'"));
     });
     return completer.future;
   }
 
   final String _name;
   int _id;
 
   SendPort _fileService;
 }
+
+List<int> _makeUint8ListView(List<int> source, int from, int to) {
+  return new Uint8List.view(source.asByteArray(), from, to);
+}