Remove 6 unused revdelete messages

Follows-up r51279 (bc35951c93df):
* revdelete-nologtype-title
* revdelete-nologtype-text
* revdelete-nologid-title
* revdelete-nologid-text

Follows-up r91346 (1c71a6f02aec) and e93fa029e2d6:
* revdel-restore-deleted
* revdel-restore-visible

Change-Id: I4276c0244076e49a62e7542eef8c662fba01d439
Merge "Remove 6 unused revdelete messages"