Server crashes because of enabled event correlation with Close new event operation.

**Issue appears in 5.2, master. Everything works in 5.0.

Steps to reproduce:

1) Create Host with item (type trap) (master_host_export.yaml added)

2) Create trigger.

3) Add tag to trigger with

name: aaa

value: ddd

4) Create event correlation with values. 

Or only with - Close new event

5) Turn on server. 

6) Create some problems events, sending to trap item. 

Result: 

Server crashes (log part added - one_more_Server_fail)

Error in console:

Expected:

No errors. No server crashes.