bug#54862: 28.1; window-text-pixel-size sometimes fails to report accurate pixel-width

[Eli Zaretskii <eliz@gnu.org>]

> From: Markus Triska <triska@metalevel.at>
> Date: Mon, 11 Apr 2022 20:48:03 +0200
> 
> 
> To reproduce this regression, please invoke Emacs with:
> 
>     $ emacs -Q
> 
> and then evaluate the following form:
> 
>     (let ((width 20))
>       (= width (let* ((height (line-pixel-height))
>                       (data (with-temp-buffer
>                               (insert (format "P1\n%s %s\n" width height))
>                               (dotimes (_ height)
>                                 (insert (make-string width ?1) "\n"))
>                               (buffer-string))))
>                  (insert " ")
>                  (let ((from (point)))
>                    (insert-image `(image :type pbm :data ,data :ascent center) "t")
>                    (car (window-text-pixel-size nil from (point)))))))
> 
> The expected result, obtained for example in Emacs 26.1 and 27.1, is: t.
> 
> Whereas with Emacs 28.1, evaluating the form unexpectedly yields: nil.

Thanks, should be fixed now on the release branch and on master.