BUG: no search result for empty labels

[Шамрай Александр]

preconditions:

* jira 8

* issue XXX-1 with empty labels

* jql query1 labels not in(SOMELABEL) and issuekey = XXX-1

* jql query2 labels != SOMELABEL and issuekey = XXX-1

expected:

* search result contains issue 

actual:

* search result is empty

works correct in jira 7

[Olga Videc]

Hello @Шамрай Александр 

I use jira 8.0.0 

And this works

tea-10 is tested environment issue key

key = "tea-10" and labels in (EMPTY, NULL)

or 

key = "tea-10" and labels= empty 

BR, Olga