Cherry picked from various commits in lua_experiment by ChrisK2.
The metrics of the OSD symbols change slightly, possibly due to the
font editor that was used, and the metrics were not correct to begin
with. (But the real reason seems unknown.) Remove the rescaling of
the OSD font in ASS_USE_OSD_FONT, because the height more or less fits
now. (This change wasn't in the lua_experiment branch.)
The old OSD font was a PostScript Type 1 font. Convert it to OpenType
to work around a fontconfig bug [1]. OpenType is a more modern format,
and the font file is quite a bit smaller, so this is actually a nice
change.
The conversion was done by opening the font with fontforge and saving
it as OpenType (CFF). fontforge showed a warning when doing this:
The font contains errors.
Self Intersecting
Bad Private Dictionary
These seem to be harmless.
[1] https://bugs.freedesktop.org/show_bug.cgi?id=63922
