anchor.diff:    }
   
     bool _close() {
  +    _closing = true;
       _socket.close();
     }
   
  
positive.code:     }
      _server = null;
      for (_HttpConnection connection in _connections) {
        connection._socket.close();
      }
      _connections.clear();
    }
  
negative.code:       int parsed = _httpParser.writeList(buffer, 0, bytesRead);
        if (parsed != bytesRead) {
          // TODO(sgjesse): Error handling.
          _close();
        }
      }
    }
  