Support auto-drain of HttpRequest data.

sdk/lib/io/http_parser.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;
 
 // Global constants.
 class _Const {
   // Bytes for "HTTP".
   static const HTTP = const [72, 84, 84, 80];
@@ skipping 560 matching lines @@
           } else {
             _incoming.statusCode = _statusCode;
             _incoming.reasonPhrase =
                 new String.fromCharCodes(_uri_or_reason_phrase);
           }
           _method_or_status_code.clear();
           _uri_or_reason_phrase.clear();
           if (_connectionUpgrade) {
             _incoming.upgraded = true;
             _parserCalled = false;
-            _controller.add(_incoming);
+            var tmp = _incoming;
+            _closeIncoming();
+            _controller.add(tmp);
             return;
           }
           if (_transferLength == 0 ||
               (_messageType == _MessageType.RESPONSE &&
                (_noMessageBody || _responseToMethod == "HEAD"))) {
             _reset();
             var tmp = _incoming;
             _closeIncoming();
             _controller.add(tmp);
             break;
@@ skipping 399 matching lines @@
   StreamController<_HttpIncoming> _controller;
   StreamController<List<int>> _bodyController;
 }
 
 
 class HttpParserException implements Exception {
   const HttpParserException([String this.message = ""]);
   String toString() => "HttpParserException: $message";
   final String message;
 }