2344: restore old get_subtitles_version code.

Not sure exatly why we need this, but it seems to be the best hack for
now.  Hopefully it holds up until we ditch tasks altogether.
2357: remove subtitle language assertion check.

For whatever reason, this isn't passing.  Hopefully the change to
get_subtitle_version() should make things work anyway.
Merge pull request #168 from pculture/x-2344

X 2344