bug#28182: maybe implement CTRL++ to zoom text

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Tue, 8 Oct 2019 23:58:09 +0200
> Cc: Eli Zaretskii <eliz@gnu.org>, Tak Kunihiro <homeros.misasa@gmail.com>, 
>       積丹尼 Dan Jacobson <jidanni@jidanni.org>, 
>       Richard Stallman <rms@gnu.org>, 28182@debbugs.gnu.org
> 
> It turns out there is already a defcustom 'mouse-wheel-follows-mouse'
> that controls this behaviour when scrolling.  If non-nil (the default)
> it will scroll the window that the mouse pointer is over, otherwise
> the one where point is.  So the job is not that hard: we should just
> do what the user wants.
> 
> The attached patch makes changing font size respect that option.  What
> do you think?

Please don't forget mentioning this in NEWS (and in the manual, if
applicable).

Thanks.