bug#20620: Mouse highlighting not removed at end of mode-line

[Eli Zaretskii]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Wed, 20 May 2015 18:02:56 -0400
> 
>    src/emacs -Q --eval "(setcdr (memq 'mode-line-buffer-identification 
> mode-line-format) nil)"
> 
> and then
> 
>    move mouse from left to right over the mode-line
> 
> When I try it, I see that as the mouse passes over "*scratch*" the
> buffer name is highlighted as it should, but once the mouse gets to the
> rest of the mode-line (which is empty) the highlighting lingers until
> the mouse actually leaves the mode-line.

Fixed in commit fc071bf.

Thanks.