Code review comment for ~athos-ribeiro/ubuntu/+source/log4cplus:add-symbols

Thanks, Andreas!

I mentioned the FFe bug in the changelog for the entry which is actually changing the list of symbols being exported.

I will forward the delta in 2 different MRs (I also already forwarded the dep8 tests in a salsa MR):

 - Setting the -fvisibility=hidden build flag. I should probably forward this upstream as well
 - Symbols files (as you said, this could be rejected right away, but it would be nice to discuss it with the maintainer).