bug#33748: 27.0.50; harfbuzz branch fails to compile

[Eli Zaretskii]

> Date: Sat, 15 Dec 2018 12:32:41 +0200
> From: Khaled Hosny <dr.khaled.hosny@gmail.com>
> Cc: behdad@behdad.org, 33748@debbugs.gnu.org, far.nasiri.m@gmail.com
> 
> > Also, if we require at least 0.9.42, then the test for
> > hb_ft_font_create_referenced, which was introduced in 0.9.38, can be
> > dropped, together with the #ifdef'ed code that relies on that test,
> > right?
> 
> Right.

OK, I see that Paul already did that, so we are fine.