bug#25105: M-p in diff-mode jumps too far

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Tino Calancha <tino.calancha@gmail.com> writes:

>>
>> I merged the bugs, and dropped #25400 from the cc list, because I'm
>> getting duplicate emails everytime.
> Thank you.  Sorry for the duplicated e-mails :-(

Hmm, I'm still getting duplicates.  Maybe I shouldn't have merged?  Oh well.

>>
>> I think the commit summary could be a bit friendlier, otherwise it looks
>> good to me.
> Thanks.  I agree: if i read my own commit after some months, probably
> i will not fully understand it.
> I propose following more verbose one:
>
> Fix Bug#17544

I was thinking more about this summary line.  And maybe add some higher
level explanation before the ChangeLog entry about the problems being
solved?