correct behavior & use of QDEL_NULL_LIST+ odd shim

code/modules/assembly/infrared.dm

@@ -39,7 +39,7 @@
 		START_PROCESSING(SSobj, src)
 	else
 		STOP_PROCESSING(SSobj, src)
-		QDEL_LIST_NULL(i_beams)
+		QDEL_NULL_LIST(i_beams)
 	return on
 
 /obj/item/assembly/infra/update_icon()
@@ -54,7 +54,7 @@
 
 /obj/item/assembly/infra/process()
 	if(!on && i_beams)
-		QDEL_LIST_NULL(i_beams)
+		QDEL_NULL_LIST(i_beams)
 		return
 
 	if(!i_beams && secured && (istype(loc, /turf) || (holder && istype(holder.loc, /turf))))
@@ -74,7 +74,7 @@
 		I.visible = visible
 
 /obj/item/assembly/infra/attack_hand()
-	QDEL_LIST_NULL(i_beams)
+	QDEL_NULL_LIST(i_beams)
 	..()
 
 /obj/item/assembly/infra/Move()
@@ -84,19 +84,19 @@
 
 /obj/item/assembly/infra/Moved(atom/old_loc, direction, forced = FALSE)
 	. = ..()
-	QDEL_LIST_NULL(i_beams)
+	QDEL_NULL_LIST(i_beams)
 
 /obj/item/assembly/infra/holder_movement()
 	if(!holder)
 		return FALSE
-	QDEL_LIST_NULL(i_beams)
+	QDEL_NULL_LIST(i_beams)
 	return TRUE
 
 /obj/item/assembly/infra/proc/trigger_beam()
 	if(!process_cooldown())
 		return FALSE
 	pulse(0)
-	QDEL_LIST_NULL(i_beams) //They will get recreated next process() if the situation is still appropriate
+	QDEL_NULL_LIST(i_beams) //They will get recreated next process() if the situation is still appropriate
 	if(!holder)
 		visible_message("[bicon(src)] *beep* *beep*")
 

code/modules/mob/mob_planes.dm

@@ -50,7 +50,7 @@
 
 /datum/plane_holder/Destroy()
 	my_mob = null
-	QDEL_LIST_NULL(plane_masters) //Goodbye my children, be free
+	QDEL_NULL_LIST(plane_masters) //Goodbye my children, be free
 	return ..()
 
 /datum/plane_holder/proc/set_vis(var/which = null, var/state = FALSE)

code/modules/shieldgen/shield_gen.dm

@@ -44,7 +44,7 @@
 	return ..()
 
 /obj/machinery/shield_gen/Destroy()
-	QDEL_LIST_NULL(field)
+	QDEL_NULL_LIST(field)
 	return ..()
 
 /obj/machinery/shield_gen/emag_act(var/remaining_charges, var/mob/user)