Fix bug in subscription handling in mime package

pkg/mime/lib/src/bound_multipart_stream.dart

 // Copyright (c) 2014, 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.
 library mime.bound_multipart_stream;
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'mime_shared.dart';
 import 'char_code.dart';
@@ skipping 87 matching lines @@
 
    // Current index in the data buffer. If index is negative then it
    // is the index into the artificial prefix of the boundary string.
    int _index;
    List<int> _buffer;
 
    BoundMultipartStream(this._boundary, Stream<List<int>> stream) {
      _controller = new StreamController(
          sync: true,
          onPause: _pauseStream,
-         onResume:_resumeStream,
+         onResume: _resumeStream,
          onCancel: () {
            _controllerState = _CONTROLLER_STATE_CANCELED;
            _tryPropagateControllerState();
          },
          onListen: () {
            _controllerState = _CONTROLLER_STATE_ACTIVE;
            _subscription = stream.listen(
                (data) {
                  assert(_buffer == null);
                  _subscription.pause();
@@ skipping 77 matching lines @@
      if (_state == _CONTENT && _boundaryIndex == 0) {
        contentStartIndex = 0;
      } else {
        contentStartIndex = null;
      }
      // The data to parse might be "artificially" prefixed with a
      // partial match of the boundary.
      boundaryPrefix = _boundaryIndex;
 
      while ((_index < _buffer.length) && _state != _FAIL && _state != _DONE) {
-       if (_multipartController != null && _multipartController.isPaused) {
-         return;
-       }
        int byte;
        if (_index < 0) {
          byte = _boundary[boundaryPrefix + _index];
        } else {
          byte = _buffer[_index];
        }
        switch (_state) {
          case _START:
            if (byte == _boundary[_boundaryIndex]) {
              _boundaryIndex++;
@@ skipping 89 matching lines @@
                _headerField.add(_toLowerCase(byte));
                _state = _HEADER_FIELD;
              }
            }
            break;
 
          case _HEADER_ENDING:
            _expectByteValue(byte, CharCode.LF);
            _multipartController = new StreamController(
                sync: true,
+               onListen: () {
+                 if (_subscription.isPaused) _subscription.resume();
+               },
                onPause: _subscription.pause,
-               onResume: () {
-                 _subscription.resume();
-                 _parse();
-               });
+               onResume: _subscription.resume);
            _controller.add(
                new _MimeMultipart(_headers, _multipartController.stream));
            _headers = null;
            _state = _CONTENT;
            contentStartIndex = _index + 1;
            break;
 
          case _CONTENT:
            if (byte == _boundary[_boundaryIndex]) {
              _boundaryIndex++;
@@ skipping 56 matching lines @@
      }
 
      // Resume if at end.
      if (_index == _buffer.length) {
        _buffer = null;
        _index = null;
        _subscription.resume();
      }
    }
 }