[cairo] pangocairo and fonts on win32

[Tor Lillqvist]

> Is it enough to load a font via AddFontResourceEx or do I have to update fontconfig as well? (so pango can find that font)

Hmm, if you are using the normal pango on Windows, no fontconfig is
involved. Only if you use pangoft2 is fontconfig involved.

But yeah, pangowin32 enumerates the fonts just once when first used in
a process (or something like that), so if you install a font after
that, I don't know how to make Pango notice. But maybe it will work
find to just try to use the font, you after all know its name, so it
shouldn't matter that it isn't in Pango's tables (and won't show up in
the GTK+ font selector)? Much of this is just speculation, I'm
afraid... experiment!

--tml