bug#57976: 29.0.50; Complex emoji have extra spacing

[Protesilaos Stavrou]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Date: Wed, 21 Sep 2022 15:35:02 +0200
>
> Protesilaos Stavrou <info@protesilaos.com> writes:
>
>> I have no reproducible recipe with harfbuzz 5.2.0 beside Emacs.  I wrote
>> the M-x emoji-list buffer to a file and visited it with a generic text
>> editor: the display looks fine.
>
> If you take one of the emojis that displayed correctly and one that was
> wrong and then say
>
> (string-pixel-width "😶‍🌫️")
>
> on both -- what does that return?  From the display, it kinda looked
> like Emacs thought that some of the glyphs were really wide.

I get these:

    (string-pixel-width "😶‍🌫️")
    ;; => 136

    (string-pixel-width "🤣")
    ;; => 16

-- 
Protesilaos Stavrou
https://protesilaos.com