bug#59862: quit-restore per window buffer

[Juri Linkov <juri@linkov.net>]

> It took me some time to rewrite the code for this since I found a couple
> of leaks in the window handling code which I tried to plug now.  In a
> nutshell, the new patch is supposed to fix the following issues.
>
> - I introduced a new variable called 'kill-buffer-quit-windows'.  If
>   non-nil, it makes killing a buffer call 'quit-restore-window' for each
>   window showing the buffer thus implementing the behavior you want.  If
>   nil, killing a buffer works as before apart from the fixes I added
>   below.

Thanks, I hope it will help to replace such configurations:

  (defun quit-window-kill-buffer ()
    "Quit WINDOW and kill its buffer."
    (interactive)
    (quit-window 1))
  (define-key special-mode-map "q" 'quit-window-kill-buffer)
  (define-key image-mode-map "q" 'quit-window-kill-buffer)
  (define-key global-map "\C-q" 'quit-window-kill-buffer)
  (define-key dired-mode-map "q" 'quit-window-kill-buffer)
  (define-key archive-mode-map "q" 'quit-window-kill-buffer)
  (define-key tar-mode-map "q" 'quit-window-kill-buffer)
  ...

I suppose it will affect only interactive uses of 'kill-buffer'.

> In earlier versions of Emacs, window configurations were mostly used to
> handle window excursions and were consequently rather short-lived.  Your
> tab bar code has changed that.  Hence we should try to avoid any leaks
> introduced by long-lived configurations.

Indeed now window configurations are long-lived, so tab-bar uses
(split-window) followed by (delete-window) to create a new window
different from the window saved in a window configuration.

> Please test the patch intensively and report any problems you see.  I
> used the forms below to test the various features of the patch.

I have used your previous patch for a long time,
and it worked perfectly.  I hope your new patch
will be as good as the old one.

PS: I noticed one difference between handling of frames and tabs:

C-x 5 5   ;; other-frame-prefix
C-h i     ;; info
C-h e     ;; view-echo-area-messages
q         ;; quit-window
This deletes the Info window, and doesn't delete the frame.
Everything is correct.

C-x t t   ;; other-tab-prefix
C-h i     ;; info
C-h e     ;; view-echo-area-messages
q         ;; quit-window
This doesn't close the tab (correct),
but doesn't delete the Info window.
This differs from the frame case that keeps
only the Messages window on the frame.