bug#12927: 24.2; global-hl-line-mode and "scroll-conservatively=1000" take jump up-down the text when hold DOWN key (in *info* buffer).

[Eli Zaretskii]

> Date: Mon, 19 Nov 2012 18:43:40 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 12927@debbugs.gnu.org
> 
> > From: Oleksandr Gavenko <gavenkoa@gmail.com>
> > Date: Sun, 18 Nov 2012 23:13:22 +0200
> > 
> >   (setq scroll-conservatively 1000)
> >   (global-hl-line-mode 1)
> > 
> > and "C-h i". I press and hold DOWN key. After some time cursor reach end of
> > frame and then text scroll up but sometimes it seems as text jump down! And 
> > I
> > get fill that text moving have jerks.
> 
> This is some bad interaction between scroll-conservatively and
> window-vscroll, it somehow succeeds to activate code paths that I
> never before saw in action.
> 
> As a temporary work-around, set auto-window-vscroll to nil.  I will
> try to find a better solution when I have time.

Should be fixed in revision 110927 on the emacs-24 branch.  Please
test.