bug#33729: 27.0.50; Partial glyphs not rendered for Gujarati with Harfbuzz enabled (renders fine using m17n)

[Eli Zaretskii]

> Date: Sun, 06 Jan 2019 19:54:24 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: behdad@behdad.org, far.nasiri.m@gmail.com, 33729@debbugs.gnu.org
> 
> > Date: Sat, 5 Jan 2019 23:04:20 +0200
> > From: Khaled Hosny <dr.khaled.hosny@gmail.com>
> > Cc: far.nasiri.m@gmail.com, behdad@behdad.org, 33729@debbugs.gnu.org
> > 
> > I pushed a couple of commits that does this based on my limited
> > understanding of Emacs code, please check.
> 
> Can you explain why you moved the call to
> hb_buffer_guess_segment_properties _after_ the code which sets some of
> the properties?  I cannot find anything about that in the HarfBuzz
> documentation.  Is this because guessing the unset properties can
> benefit from knowing the properties which _are_ set, such as the
> direction?
> 
> I did it the other way around, because my mental model was: first set
> the defaults, then override them where better info is available.
> 
> Thanks.

Please respond.