bug#46904: Non-unique windows produced by window-state-put

[Juri Linkov]

tags 46904 fixed
close 46904 28.0.50
thanks

>>> When 'frame-root-window' returns an internal window,
>>> then we don't put the state into the root window anyway,
>>> we create a new window.  The patch does the same for the
>>> case when there is only one window too, so both cases
>>> will provide the same consistent result.
>>
>> Yes.  But how would you handle `window-swap-states' now?
>
> No changes are planned in window.el, only in tab-bar.el.

Now pushed to master in commit 29458ec7d2.