bug#27569: delete-selection on yank via popup-menu

[Tak Kunihiro <tkk@misasa.okayama-u.ac.jp>]

>> I want to yank via popup-menu with delete-selection-mode.
>> Problem is yanking via popup-menu does not delete region.
>>
>> emacs -Q
>> (defun popup-edit-menu ()
>>  (interactive)
>>  (popup-menu menu-bar-edit-menu))
>> (define-key global-map [mouse-3] 'popup-edit-menu)
>> (delete-selection-mode 1)
>>
>> 1. kill something
>> 2. select text (activate region) to be replaced
>> 3. choose yank in popup-menu via mouse-3
>>
>> Problem: Selected text by (2) is not deleted.
>>
>> I barely see problem is that on delete-selection-pre-hook,
>> this-command is `popup-edit-menu' instead `yank'.
>>
>> Is there a way to solve the problem?
> 
> This seems to work, though I'm not sure if it's the right way.  Perhaps
> `this-command' should be setq instead of let-bound?  Will running
> pre-command-hook twice be a problem? etc...
> 
> --- i/lisp/menu-bar.el
> +++ w/lisp/menu-bar.el
> @@ -2360,6 +2360,8 @@ (defun popup-menu (menu &optional position prefix from-menu-bar)
>        ;; `setup-specified-language-environment', for instance,
>        ;; expects this to be set from a menu keymap.
>        (setq last-command-event (car (last event)))
> +      (let ((this-command cmd))
> +        (run-hooks 'pre-command-hook))
>        ;; mouse-major-mode-menu was using `command-execute' instead.
>        (call-interactively cmd))))

Although I cannot comment on what you worry, it works well for me.
Thank you for the fix.