bug#51821: 29.0.50; Suggest add variable or frame parameter: line-height

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: tumashu@163.com,  luangruo@yahoo.com,  51821@debbugs.gnu.org
> Date: Sun, 21 Nov 2021 09:21:25 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> If we're going to be scaling stuff, it'd be nice if there was a setting
> >> that was clearly non-scaleable.  An integer value to :height would be
> >> possible, but pretty error-prone
> >
> > How is something like ":height 1" error-prone?
> 
> Because people aren't expecting ":height 1" and ":height 1.0" to have
> such different semantics.

??? That ship has sailed long ago, in Emacs 21.  Float values and
integer values have different meanings in these face attributes (and
in other similar features, like line-height, the "space :height"
display spec, etc.).  Why is this suddenly a problem, and one that
requires a new face attribute at that?