base.fill_sack(): add skip_if_unavailable argument (RhBug:1189083)

[jsilhan]

No description provided.

[ghost]

Why it has to be in fill_sack? =-O It doesn't make a sense to me. Why should we modify repositories when creating a sack? I think this is not correct place for convenient setting of all repositories. If it is needed at all, I think it should be in RepoDict. Otherwise, the number of arguments of fill_sack is going to raise infinitely.

I think that for the bug it would be enough to add skip_if_unavailable to API. I think that we will need to add it there anyway since it is already configurable from dnf.conf.

[timlau]

something like self.repos.all().set_skip_if_unavailable(True) could be a way to set this flag for alle repos. I agree it feels misplaced in fill_sack

[jsilhan]

Right, Repo.skip_if_unavailable added to API in commit 05b03fc.