bug#44784: Combining accent is not combining

[Eli Zaretskii]

> From: Stephen Berman <stephen.berman@gmx.net>
> Cc: juri@linkov.net,  44784@debbugs.gnu.org
> Date: Sun, 22 Nov 2020 17:28:09 +0100
> 
> FTR, here's what `C-u C-x =' shows for the correct and incorrect
> displays, respectively:
> 
> Composed with the following character(s) "́" using this font:
>   ftcrhb:-PfEd-DejaVu Sans-normal-normal-normal-*-13-*-*-*-*-0-iso10646-1
> by these glyphs:
>   [0 1 1110 243 4 1 3 7 0 nil]
>   [0 1 769 690 0 -5 -1 11 -7 [1 0 0]]
> with these character(s):
>   ́ (#x301) COMBINING ACUTE ACCENT
> 
> Composed with the following character(s) "́" using this font:
>   ftcrhb:-PfEd-DejaVu Sans Mono-normal-normal-normal-*-13-*-*-*-m-0-iso10646-1
> by these glyphs:
>   [0 1 1110 917 8 1 8 10 0 nil]
>   [0 1 769 649 8 3 8 11 -8 [0 0 0]]
> with these character(s):
>   ́ (#x301) COMBINING ACUTE ACCENT

OK, zero WIDTH and negative LBEARING/RBEARING is another way to place
the accent correctly.