Kibana version:
6.4.0

Elasticsearch version:
6.4.0

Server OS version:
Cloud

Browser version:
Chrome Version 68.0.3440.106 (Official Build) (64-bit)

Browser OS version:
OSX 10.13.6

Original install method (e.g. download page, yum, from source, etc.):
Cloud

Describe the bug:
When Derivative aggregation gets in an erroneous state, it can't be fixed by fixing the error.

Steps to reproduce:

1. Create a simple derivative graph with a date histogram
   

Make any "mistake" (I thought it was possible to create a split chart with derivative...)

3. Then I fix the "mistake" by removing the split aggregation, but the error state is still showing:
   

The tooltip just shows:

And hovering over the red box doesn't show anything.

Whatever I do I can't repair that error. If I create a new visualization from scratch without doing any mistakes the same visualization works again.

Expected behavior:
To be able to recover from errors

Errors in browser console (if relevant):
None

Any additional context: