I have no idea how the previous formula was supposed to work at all, but
this one is the same as our alignof code to make sure we do allocate to
the really nearest size and don't do over allocation. Additionnaly it works.
eina_array_remove() didnt ever realloc down unless we went to 0
members. this wasn't very good as you'd expect the array to be reduced
in size if enough items were removed. not only that the old code was
stupid and ALWAYS malloc()ed a new array of the exact same size and
copied items over in the most complex way possible, then freed the old
one. this would have added overhead wherever used (evas_render) that
should not have been there.
this is based on the idea in a patch from
Viacheslav Lvov <v.lvov@samsung.com>, but this is a re-do of it
entirely, reducing the codebase massively even compared to the patch
and making it much simpler to read, maintain, actually reduce memory
and cut overhead.