bug#21243: 25.0.50: cannot insert thin line

[Eli Zaretskii]

> From: Jonas Bernoulli <jonas@bernoul.li>
> Date: Wed, 12 Aug 2015 16:40:37 +0200
> 
> It used to be possible to insert a thin line like this:
> 
>   (insert (propertize (concat (propertize "\s" 'display '(space :height (1)))
>                               (propertize "\n" 'line-height t))
>                       'face 'magit-diff-added))
> 
> In v25.0.50 (build today) this no longer works.

Thanks, I fixed this.