Minor changes to the dart:io library files.

runtime/bin/file_impl.dart

 // Copyright (c) 2012, 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.
 
 class _FileInputStream extends _BaseDataInputStream implements InputStream {
   _FileInputStream(File file) {
     _file = file.openSync();
     _length = _file.lengthSync();
     _streamMarkedClosed = true;
     _checkScheduleCallbacks();
@@ skipping 76 matching lines @@
     }
   }
 
   RandomAccessFile _file;
 }
 
 
 class _FileOperation {
   abstract void execute(ReceivePort port);
 
-  SendPort set replyPort(SendPort port) {
+  void set replyPort(SendPort port) {
     _replyPort = port;
   }
 
   bool isWrite() => false;
 
   SendPort _replyPort;
 }
 
 
 class _ExistsOperation extends _FileOperation {
@@ skipping 474 matching lines @@
       handler = (file) => file.close();
     }
     var handleOpenResult = (id, ignored) {
       if (id != 0) {
         var randomAccessFile = new _RandomAccessFile(id, _name);
         handler(randomAccessFile);
       } else if (_errorHandler != null) {
         _errorHandler("Cannot open file: $_name");
       }
     };
-    var operation = new _OpenOperation(_name, mode.mode);
+    var operation = new _OpenOperation(_name, mode._mode);
     _scheduler.enqueue(operation, handleOpenResult);
   }
 
   RandomAccessFile openSync([FileMode mode = FileMode.READ]) {
     if (_asyncUsed) {
       throw new FileIOException(
           "Mixed use of synchronous and asynchronous API");
     }
     if (mode != FileMode.READ &&
         mode != FileMode.WRITE &&
         mode != FileMode.APPEND) {
       throw new FileIOException("Unknown file mode. Use FileMode.READ, " +
                                 "FileMode.WRITE or FileMode.APPEND.");
     }
-    var id = _FileUtils.checkedOpen(_name, mode.mode);
+    var id = _FileUtils.checkedOpen(_name, mode._mode);
     if (id == 0) {
       throw new FileIOException("Cannot open file: $_name");
     }
     return new _RandomAccessFile(id, _name);
   }
 
   void fullPath() {
     _asyncUsed = true;
     var handler = _fullPathHandler;
     if (handler == null) handler = (path) => null;
@@ skipping 464 matching lines @@
   var _readByteHandler;
   var _readListHandler;
   var _noPendingWriteHandler;
   var _positionHandler;
   var _setPositionHandler;
   var _truncateHandler;
   var _lengthHandler;
   var _flushHandler;
   var _errorHandler;
 }