anchor.diff:        }
         _server = await HttpServer.bind(address, _port);
         _server.listen(_requestHandler, cancelOnError: true);
  -      print('Observatory listening on $serverAddress');
  +      serverPrint('Observatory listening on $serverAddress');
         // Server is up and running.
         _notifyServerState(serverAddress.toString());
         onServerAddressChange('$serverAddress');
         return this;
       } catch (e, st) {
  -      print('Could not start Observatory HTTP server:\n$e\n$st\n');
  +      serverPrint('Could not start Observatory HTTP server:\n$e\n$st\n');
         _notifyServerState("");
         onServerAddressChange(null);
         return this;
  
positive.code: // BSD-style license that can be found in the LICENSE file.
  
  part of vmservice_io;
  
  class WebSocketClient extends Client {
    static const int PARSE_ERROR_CODE = 4000;
  
negative.code:     // Shutdown HTTP server and subscription.
      Uri oldServerAddress = serverAddress;
      return cleanup(forced).then((_) {
        serverPrint('Observatory no longer listening on $oldServerAddress');
        _server = null;
        _notifyServerState("");
        onServerAddressChange(null);
        return this;
      }).catchError((e, st) {
        _server = null;
        serverPrint('Could not shutdown Observatory HTTP server:\n$e\n$st\n');
        _notifyServerState("");
        onServerAddressChange(null);
        return this;
  