bug#24563: kill-region fails while dragging a selection

[Eli Zaretskii <eliz@gnu.org>]

> From: Phil Ruffwind <rf@rufflewind.com>
> Date: Wed, 28 Sep 2016 14:30:44 -0400
> 
> Emacs 25.1 seems to have changed the behavior of doing kill-region (C-w)
> while dragging a selection in GUI mode.  Here are the steps to
> reproduce:
> 
>  1. Run Emacs in GUI mode via: emacs -Q
>  2. Type: M-x set-variable mark-even-if-inactive nil
>  3. Open a file containing some text.
>  4. Make a selection using the mouse, but do NOT release the mouse
>     button.
>  5. Type: C-w.
> 
> In Emacs 24.5, this would initially do nothing, but pressing C-w a
> second time will kill the selected region correctly.
> 
> In Emacs 25.1, this fails with "The mark is not active now" and
> deselects the region.

Why is this a bug?  Neither of the two behaviors is AFAIK documented,
so either could be correct.  I agree that the behavior changed, most
probably because both the implementation of region highlight and the
binding of commands to the mouse have changed in Emacs 25.1.  But is
there a reason not to get along with the new behavior?

Thanks for reporting this.