* keyboard.c (Qmenu_alias, Vdefine_key_rebound_commands): Remove.

* keyboard.c (Qmenu_alias, Vdefine_key_rebound_commands): Remove.
(parse_menu_item): Streamline since bindings are recomputed all the
time anyway.  Don't bother checking Vdefine_key_rebound_commands any
more and don't support lmenu's menu-alias any more either.
* subr.el (define-key-rebound-commands): Mark obsolete.
* startup.el (precompute-menubar-bindings): Remove.
(normal-top-level): Remove obsolete code that tried to precompute
menubar bindings.
* loadup.el (define-key-rebound-commands): Don't bother fiddling with
define-key-rebound-commands and precompute-menubar-bindings.