bug#47300: delete-window to select window with same position

[martin rudalics]

>> People still have trouble with unpredictable behavior of 'C-x 0'
>> that selects an unexpected window after the current window is deleted.
>>
>> This is a recent example:
>> 
https://old.reddit.com/r/emacs/comments/m8omt0/how_can_deletewindow_cx_0_be_configured_to_stay/
>>
>> The previous failed attempt to fix this was in bug#32790.
>>
>> I still don't understand the current logic what window is selected
>> after deleting the selected window with 'C-x 0'.

By design it's the most recently used window (`get-mru-window') on the
same frame after the deleted window has been removed from its window
tree.

> `C-x 0' isn't a command I use much, so I don't really have much
> intuition about how it's supposed to work.  But, indeed, playing around
> with it, it seems unexpected that `C-x 0' selects a different window
> (instead of remaining in the "merged" window).
>
>> Maybe something like this could be adapted to delete-window
>> by adding an optional interactive argument keep-pos:
>
> If I'm reading that patch correctly (I haven't actually tested), that
> seems more DWIM to me.  Perhaps Martin has some comments here; added to
> the CCs.  (And if anybody else has an opinion here, please do chime in.)

Personally I don't care but people used to the current behavior might
get confused.  So an option should be the provided and could be "ON" by
default.

martin