event-handler: Do not die if !action->leave_.
event-handler: Do not die if !action->leave_.

	* src/object/event-handler.cc (stop): Check leave_ for 0
        before using it.

urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,aldebaran/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi