bug#30955: 27.0.50; Mouse clicks on header-line in Info are broken

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Monnier <monnier@IRO.UMontreal.CA>
> Cc: 30955@debbugs.gnu.org, m43cap@yandex.com
> Date: Thu, 29 Mar 2018 09:11:41 -0400
> 
> >> There's indeed a bug, here, which is that it says
> >> 
> >>     (translated from <mouse-2>)
> >> 
> >> instead of
> >> 
> >>     (translated from <mouse-1>)
> >> 
> >> I assume it's because the fix I installed modifies the event in-place,
> >> so the recording of "untranslated events" gets changed by side-effect.
> >
> > I don't think so: I saw the mouse-2 part even before you fixed the
> > problem.
> 
> Maybe you've seen it with yet-older code, such as the one in the
> emacs-26 branch (in that code, the mouse-1 => mouse-2 remapping was done
> elsewhere (i.e. as part of the processing of down-mouse-1) so
> read_key_sequence never even saw the mouse-1 event to put it into the
> raw_keybuf)?
> 
> > So I think it's something else at work.
> 
> Yet the second hunk below does fix this problem (the first hunk fixes
> the same problem but for C-h l, and the third just removes code which
> does something wrong, and I have no idea why the code was there in the
> first place).

AFAICT, this patch is now installed on master, but I still see the
same issue: "C-h c" reports mouse-2 whereas I click mouse-1.  Was this
issue supposed to be resolved, and if so, what am I missing?