bug#56357: Request for font size adaptation that fits window

[Eli Zaretskii <eliz@gnu.org>]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: carlmarcos@tutanota.com,  56357@debbugs.gnu.org
> Date: Mon, 04 Jul 2022 15:54:44 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > With your proposal, how would you determine the target value?  If it's
> > just an arbitrary value (80 sounds like an arbitrary one to me), then
> > the recently-added global-text-scale-adjust-resizes-frames variable
> > does the same, just from the other end: the user enlarges the font and
> > the frame follows suit.  And since our default frame width is already
> > set for 80 characters, it sounds like we already have the feature you
> > envisioned, no?
> 
> I think the user wants to be able to drag a frame to be bigger and get
> the font to be resized to have the same number of columns, so it's not
> the same feature at all.

I'm asking why it matters how you "drag the frame": whether by
actually dragging its edge or by C-M-wheel-up.  The results is the
same, no?

And that actually gives an idea: make dragging the frame call the same
function that C-M-wheel-up does.