bug#28864: 25.3.50; next-error-no-select does select

[Juri Linkov <juri@linkov.net>]

>> It's really a hack though, right? Maybe no major modes should set
>> next-error-last-buffer by itself, no matter the current command.
> That sounds better.
>> I'd like to know what Juri thinks about this.
> In case Juri think that change-log-mode should keep seting
> next-error-last-buffer for other reasons we could just
> bind next-error-last-buffer:

Visiting a buffer should not set next-error-last-buffer,
it should be set only by an explicit user request,
like M-x compile/grep/rgrep/occur and other commands do.

So please just remove setting of next-error-last-buffer
from change-log-mode.  After that, next-error will still remain
available in ChangeLog buffers by running ‘next-error’ (when
there are no other next-error capable buffers such as *grep*)
or explicit C-c C-c that will set next-error-last-buffer
and continue visiting matches from the ChangeLog buffer.

We also have other issues with next-error in bug#20489
where I'm waiting when Dmitry will send a comprehensive list
of possible scenarios, so we could find a solution that fits
all of them.

Regarding the ChangeLog buffers, I have a solution for
the following ChangeLog-related scenario:

1. M-x grep-find RET
   find . -type f -name ChangeLog\* -exec grep --color -nH -e baz {} + RET

2. C-x o RET M-n RET

3. M-g M-n should continue visiting next grep hits from the *grep* buffer

4. When the user needs to switch to visiting ChangeLog entries
   from the ChangeLog buffer, this can be achieved by typing
   C-c C-c (change-log-goto-source) once, then all subsequent
   M-g M-n will continue visiting next ChangeLog entries
   in the source files.