bug#34035: 26.1; Arabic shadda-kasrah renders incorrectly

[Eli Zaretskii]

> From: James Cloos <cloos@jhcloos.com>
> Cc: "Basil L. Contovounesios" <contovob@tcd.ie>,  34035@debbugs.gnu.org,
>   stefan@marxist.se,  craven@gmx.net
> Date: Sun, 23 Aug 2020 02:41:09 -0400
> 
> i bet this is the same as the regression i posted a while back where
> cr+hb fails to handle fully mono fonts whereas the xft-based code does
> handle them.
> 
> i suspect m17n-lib had the necessary code, whereas hb lazily only cares
> aboutfonts with zero-width accents or with routines *in* each font
> correctly to combine glyphs.

I don't understand why you consider this a regression.  For the
shadda-kasrah case, the experts seem to unanimously say that both
renderings are possible and correct, and which one is used is a
stylistic preference.