bug#19576: write-file writes the wrong buffer

[Eli Zaretskii <eliz@gnu.org>]

> Date: Sat, 21 Nov 2015 19:27:38 +0100
> From: martin rudalics <rudalics@gmx.at>
> CC: Alan Mackenzie <acm@muc.de>, 19576@debbugs.gnu.org, 
>  Juri Linkov <juri@linkov.net>
> 
> Resizing a frame calls ‘window-configuration-change-hook’ instead.  In
> Emacs 22 change_frame_size_1 still had
> 
>    /* This isn't quite a no-op: it runs window-configuration-change-hook.  */
>    Fset_window_buffer (FRAME_SELECTED_WINDOW (f),
> 		      XWINDOW (FRAME_SELECTED_WINDOW (f))->buffer, Qt);
> 
> while in Emacs 23 change_frame_size_1 already uses
> 
>    run_window_configuration_change_hook (f);
> 
> Obviously ‘window-size-change-functions’ seems more logical here but
> might break packages that expect the old behavior.  Running both hooks
> for frame resizes doesn't seem overly clever but we do so already when
> deleting and splitting windows.  Anyway, this is a can of worms.

We could run both types of hooks, couldn't we?  The documentation
seems to suggest that both of them should be run in this situation.

As for "can of worms", we could make that change on master and see
what breaks.  WDYT?