don't report callbacks on NULL object.
don't report callbacks on NULL object.

From _del_pre_hook() we first delete pan_smart and then call
elm_genlist_clear() to rip off children, however genlist_clear was
always doing evas_object_smart_callback_call() on it.



SVN revision: 52111

rvandegrift/elementary,FlorentRevest/Elementary,tasn/elementary,tasn/elementary,tasn/elementary,FlorentRevest/Elementary,FlorentRevest/Elementary,rvandegrift/elementary,tasn/elementary,tasn/elementary,FlorentRevest/Elementary,rvandegrift/elementary,rvandegrift/elementary