bug#43645: 26.3; emacsclient -c does not open to correct window

[Eli Zaretskii <eliz@gnu.org>]

> Cc: bluetrack121@gmail.com, 43645@debbugs.gnu.org
> From: martin rudalics <rudalics@gmx.at>
> Date: Mon, 28 Sep 2020 17:02:13 +0200
> 
>  >> diff --git a/lisp/server.el b/lisp/server.el
>  >> index 436a6ca0c7..f24f8d2b7c 100644
>  >> --- a/lisp/server.el
>  >> +++ b/lisp/server.el
>  >> @@ -1602,7 +1602,7 @@ server-switch-buffer
>  >>         ;; OK, we know next-buffer is live, let's display and select it.
>  >>         (if (functionp server-window)
>  >>   	  (funcall server-window next-buffer)
>  >> -	(let ((win (get-buffer-window next-buffer 0)))
>  >> +	(let ((win (get-buffer-window next-buffer)))
>  >>   	  (if (and win (not server-window))
>  >>   	      ;; The buffer is already displayed: just reuse the
>  >>   	      ;; window.  If FILEPOS is non-nil, use it to replace the
>  >>
>  >
>  > Martin, any comments on this?
> 
> Wouldn't the "0" make sense when invoking emacsclient without an option
> like -c or -t?  IIUC, in that case we should try to reuse some existing
> visible or iconified window.  But ... I never use emacsclient.

Lars, can you try Martin's proposal and see if it solves the problem
without any adverse side effects on other use cases?

Thanks.