anchor.diff:  
       var connection = new Connection(
           'proj_id',
  -        (http.BaseRequest request) {
  -          return new MockClient.streaming(streamHandler).send(request);
  -        }
  +        new MockClient.streaming(streamHandler)
       );
   
       connection.logger.onRecord.listen(print);
  
positive.code: 
        var connection = new Connection(
            'proj_id',
            (http.BaseRequest request) {
              return new MockClient.streaming(streamHandler).send(request);
            }
        );
  
        var src = new StringSource("abcdefghijklmnopqrstuvwxyz");
  
negative.code: 
        var connection = new Connection(
            'proj_id',
            new MockClient.streaming(streamHandler)
        );
  
        //connection.logger.onRecord.listen(print);
  