bug#10539: 24.0.92; low display-time-interval makes Emacs slow

[Eli Zaretskii]

> Date: Sun, 29 Jan 2012 18:51:42 +0100
> From: martin rudalics <rudalics@gmx.at>
> CC: Glenn Morris <rgm@gnu.org>, michael_heerdegen@web.de, 
>  10539@debbugs.gnu.org
> 
>  > Calling force-mode-line-update with ALL non-nil forces a more thorough
>  > redisplay (because it sets a flag which causes redisplay not to trust
>  > the contents of the displayed windows, not just their mode lines).
> 
> Can you tell me which flag (with-current-buffer (other-buffer)) sets?

windows_or_buffers_changed, AFAIR.