bug#12204: 24.1.50; Binding mouse-movement interferes with "C-h c" for mouse clicks

[Eli Zaretskii <eliz@gnu.org>]

> From: npostavs@users.sourceforge.net
> Cc: 12204@debbugs.gnu.org
> Date: Sat, 24 Jun 2017 23:18:03 -0400
> 
> >> > I was actually thinking seriously to not show the help message for
> >> > mouse-movement bindings.  Would that break something important?
> >> 
> >> It should only break discovery of what's bound to <mouse-movement> I
> >> guess, and we could still leave "C-h k" for that so it shouldn't be
> >> much of a problem.
> >
> > Then I think this is what we should do, and perhaps leave some knob to
> > get back the old behavior.
> 
> Here are some patches, the first deduplicates the code of describe-key
> and describe-key-briefly since they had some almost-identical sections
> that confused me when I started by accidentally modifying the wrong one.
> 
> The second patch just ignores mouse-movement for "C-h c", I don't think
> it's worth an option to get the old behaviour, but it's easy enough to
> add it if you want.

Thanks, please install if no objections come up in a few days, and
let's see if someone hollers.