bug#13055: 24.3.50; `scroll-margin' not always honored in Info buffers

[Eli Zaretskii <eliz@gnu.org>]

> From: Juanma Barranquero <lekktu@gmail.com>
> Date: Mon, 3 Dec 2012 17:09:28 +0100
> Cc: Eli Zaretskii <eliz@gnu.org>, 13055@debbugs.gnu.org
> 
> On Mon, Dec 3, 2012 at 4:21 PM, Dani Moncayo <dmoncayo@gmail.com> wrote:
> 
> > What's the point of distinguishing "motion" and "scrolling" here?
> 
> Not all motions are scrolling. Though, to be fair, Emacs seems to be
> treating most of them like scrolls in the sense of honoring
> scroll-margin.

But this one is not motion at all.  Not even remotely.  It discards
previous text and fills the buffer with an entirely new one.

It is immaterial that Backspace is bound to the command called
'Info-scroll-down'.  What that command does is go to the previous node
in the graph structure of the manual.  The "previous" node could be
anywhere in the manual, since an Info manual does not have a flat
linear structure.  You go to a different section, chapter, or even
another manual -- all according to what the author put in the Prev
link.  It's absurd to call this "scrolling".