bug#71085: text-scale-adjust does not adjust margin width

[Eli Zaretskii <eliz@gnu.org>]

> From: Emre Yolcu <mail@emreyolcu.com>
> Date: Tue, 21 May 2024 16:10:14 -0400
> Cc: 71085@debbugs.gnu.org
> 
> > Actually, you want a face that will _not_ be remapped, since you want
> > to make sure the text in the margins will not get clipped.  The
> > current behavior is that by default the text in the margin is already
> > remapped, which is why it can get clipped if it becomes too wide.
> By remap here I mean that it will remap the margin face *back* to the  
> original height. The current behavior does not explicitly touch (remap)  
> the text in the margin, so the height gets determined by the buffer-local  
> height of the default face.

Which means the text in the margins is "remapped" together with the
rest of buffer text.  While you want it to retain its original size,
so as not to be clipped.

> If enabled, the option would make text-scale-mode remap the margin
> face back to the original height to prevent the text from getting
> clipped.

We don't have "remapping back" in Emacs.  Face remapping affects the
same all the faces that don't have an absolute size specification, so
they all grow or shrink in the same manner.  The only faces that don't
grow/shrink are those which are NOT remapped or have an absolute size
spec.