bug#64752: 30.0.50; proced: text-scale-adjust leads to wrong header alignment

[Eli Zaretskii]

> From: Matthias Meulien <orontee@gmail.com>
> Date: Thu, 20 Jul 2023 21:43:40 +0200
> 
> 1. M-x proced
> 
> 2. C-x C-- (to call text-scale-adjust)
> 
> 3. Observe the header text scale has not changed while the columns text
> scale has. This leads in wrong alignment of columns labels.

Thanks, should be fixed now on the master branch.  (The fix includes a
change in the display engine, as one of the sub-features of the
:align-to display spec turned out to have a subtle bug which affected
the fix of the Proced display.)

In general, the main reason for this bug is that we don't by default
remap the header-line face (because many Lisp programs don't want
that) under text-scale-adjust.  If a Lisp program wants the
header-line to be scaled together with buffer text, it should request
that explicitly by setting text-scale-remap-header-line non-nil.