bug#34723: 27.0.50; customize and improve diff-mode recentering

[Eli Zaretskii]

> Date: Tue, 05 Mar 2019 20:49:13 +0100
> From: charles@aurox.ch (Charles A. Roelli)
> CC: 34723@debbugs.gnu.org
> 
> The function diff-hunk-next is defined using the macro
> easy-mmode-define-navigation, and its definition calls (recenter '(0))
> too liberally.  The call also ignores settings like
> 'scroll-conservatively'.  The display engine is not at fault, and we
> should be able to fix the issue either in easy-mmode or in diff-mode.

I don't understand what calling 'recenter' has to do with
scroll-conservatively.  And scroll-conservatively is implemented in
the display engine, so I'm afraid I'm still in the dark regarding the
nature of the problem you are discussing.

Of course, if you know what to do to fix the problem, there's no need
for me to understand the issue, and I should just shut up and let you
do what you think is right.

Thanks.