bug#62032: 28.2; `switch-frame' event exits incremental search

[Eli Zaretskii <eliz@gnu.org>]

> Date: Tue, 07 Mar 2023 12:38:45 +0100
> From:  "Farblos" via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> Not sure whether bug or feature ...
> 
> Start emacs as "emacs -Q".  Then:
> 
> ;; open second frame
> C-x 5 b *Messages* RET
> 
> ;; switch back to first frame showing scratch buffer
> C-x 5 o 
> 
> ;; go to beginning of scratch buffer
> ESC <
> 
> ;; isearch for "buffer"
> C-s buffer
> 
> <switch to the second Emacs frame by window manager means, for example, M-Tab>
> 
> The last step on my Emacs would exit the incremental search on the first Emacs frame.
> 
> >From this comment in isearch.el:
> 
>     ;; Pass frame events transparently so they won't exit the search.
>     ;; In particular, if we have more than one display open, then a
>     ;; switch-frame might be generated by someone typing at another keyboard.
>     (define-key map [switch-frame] nil)
>     (define-key map [delete-frame] nil)
>     (define-key map [iconify-frame] nil)
>     (define-key map [make-frame-visible] nil)
>     (define-key map [mouse-movement] nil)
>     (define-key map [language-change] nil)
> 
> I would deduce that this should not happen.
> 
> When I bind #'ignore to [switch-frame] instead of nil things work as expected (by me).

Juri, could you please look into this?