Bug#943724: lintian: internal error in Lintian::files::empty_package::_set_is_dummy

[intrigeri <intrigeri@boum.org>]

Control: tag -1 + patch

Hi,

I believe I partly understood the bug. I did not dive into why it does
not happen in all cases; but I suspect this has to do with the recent
librole-tiny-perl updates. Regardless, my understanding is that the
affected Lintian code was not entirely correct, and used to work
merely by luck, while my proposed fix makes it more correct and
robust:

https://salsa.debian.org/lintian/lintian/merge_requests/266

Cheers!