Github user MikeThomsen commented on the issue:
https://github.com/apache/nifi/pull/2699
@bartektartanus It fails `TestValidateXml`. If you run those tests, you'll
see that your update doesn't include the `evaluateExpressionLanguage` calls
that are needed to pass validation. So please run those tests and you'll see
where you need to add some extra fixes to flesh this out.---
