[Fontconfig] fc-cache sometimes looses fonts

[Patrick Lam]

Patrick Lam wrote:
> I added an extra FcDirScan to this codepath.  I believe that this fixes
> the cache corruption problems.  I hate to admit that I'm not entirely
> sure why the old code had cache corruption problems, but I'll look into
> that just a bit longer.  It seems to make sense though.

Of course, when you think you don't really understand what's going on,
there's a good chance it's because you actually don't understand what's
going on.  The problem really was in re-serializing already-serialized
FcValues; I forgot a canonicalization there, so that it was writing out
garbage pointers.  I've committed a one-line fix and reverted the
previous patch (which would of course always mask the problem).  So the
losing-font problem and the corrupted font cache problem should both be
fixed now.

I think this calls for 2.3.92, which I'll try to release tomorrow
morning.  Are there any other issues that I should address (possibly
post-2.3.92)?

pat