Update options like --sub-text-margin-y at runtime. These are somewhat
of a problem, because ass_set_selective_style_override() (intentionally)
does not override them. This should be fixed in libass (by providing
additional override modes), but for now this will do.
Also change the signature of mp_ass_configure(), so we can get access to
the track.
Additionally, drop the redundant setting of the style Alignment (it's
overwritten by mp_ass_set_style()).
See #1622 (again).
wm4
dbc5d7b7db