bug#68235: 29.1.90; Switching tabs stops following process output in selected window

[Juri Linkov]

>> So we'd need a persistent window parameter
>>
>> (1) whose value is set to dired's file name at point in
>> 'current-window-configuration'
>>
>> (2) and allows to restore the window's point appropriately in
>> 'set-window-configuration'.
>
> I now think that we need two or three hooks:
>
> - 'pre-current-window-configuration-functions', an abnormal hook that
>   receives one argument - the frame whose configuration shall be
>   recorded.  'dired' has to set a persistent window parameter, for each
>   window on that frame it uses, whose value is whatever is needed to
>   restore the present state of the buffer in that window.

Actually one hook 'pre-current-window-configuration-functions' should be
sufficient.  Like there is only 'isearch-push-state-function' that can
be used to save a lambda that can restore the current window-start, then
on going back this lambda is called and restores the previous window-start.