Crash on the subsequence removing while a restriction site is selected in a circular view

Scenario to reproduce:

1. Open "data/samples/FASTA/human_T1.fa".
2. Toggle a Circular View for the sequence.
3. Find some restriction sites.
4. Select any restriction site in the "Restriction Sites Map" widget.
5. Remove a part of the sequence that contains the selected site.
   Expected state: the sequence is modified, enzymes list is updated.
   Current state: UGENE sometimes crashes on this operation.

If you can't reproduce the crash try to repeat the scenario several times.