Comment and white-space cleanup in IO libraries.

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 935 matching lines @@
   void setPositionSync(int position) {
     if (_asyncUsed) {
       throw new FileIOException(
           "Mixed use of synchronous and asynchronous API");
     }
     bool result = _FileUtils.setPosition(_id, position);
     if (result == false) {
       throw new FileIOException("setPosition failed");
     }
   }
-  
+
   void truncate(int length) {
     _asyncUsed = true;
     var handler = (_truncateHandler != null) ? _truncateHandler : () => null;
     var handleTruncateResult = (result, ignored) {
       if (result == false && _errorHandler != null) {
         _errorHandler("truncate failed");
         return;
       }
       handler();
     };
@@ skipping 115 matching lines @@
   var _readByteHandler;
   var _readListHandler;
   var _noPendingWriteHandler;
   var _positionHandler;
   var _setPositionHandler;
   var _truncateHandler;
   var _lengthHandler;
   var _flushHandler;
   var _errorHandler;
 }