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

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Date: Sun, 14 Nov 2021 02:23:46 +0100
> Cc: 51821@debbugs.gnu.org
> 
> "Feng Shu" <tumashu@163.com> writes:
> 
> > Maybe we should add a variable or frame parameter: line-height
> 
> Sounds good to me.  Perhaps call it min{imum,}-line-height, though.

IMO it should be line-height, for similarity with line-spacing.