correct mixed case QDEL_NULL/qdel_null + behavior

code/modules/client/client procs.dm

@@ -424,7 +424,7 @@
 	winset(src, null, "outputwindow.htmloutput.is-visible=false;outputwindow.oldoutput.is-visible=false;outputwindow.chatloadlabel.is-visible=true")
 
 	//The hard way
-	qdel_null(src.chatOutput)
+	QDEL_NULL(src.chatOutput)
 	chatOutput = new /datum/chatOutput(src) //veechat
 	chatOutput.send_resources()
 	spawn()

code/modules/holomap/mapper.dm

@@ -112,7 +112,7 @@
 	
 	map_image_cache.Cut()
 	icon_image_cache.Cut()
-	qdel_null(extras_holder)
+	QDEL_NULL(extras_holder)
 
 	return ..()
 

code/modules/integrated_electronics/subtypes/output.dm

@@ -502,7 +502,7 @@
 	QDEL_NULL(hologram)
 
 //	holo_beam.End()
-//	qdel_null(holo_beam)
+//	QDEL_NULL(holo_beam)
 
 	power_draw_idle = 0
 

code/modules/mob/living/simple_mob/subtypes/mechanical/mecha/mecha.dm

@@ -59,7 +59,7 @@
 	return ..()
 
 /mob/living/simple_mob/mechanical/mecha/Destroy()
-	qdel_null(sparks)
+	QDEL_NULL(sparks)
 	return ..()
 
 /mob/living/simple_mob/mechanical/mecha/death()

code/modules/modular_computers/hardware/battery_module.dm

@@ -71,7 +71,7 @@
 	. = ..()
 
 /obj/item/computer_hardware/battery_module/Destroy()
-	qdel_null(battery)
+	QDEL_NULL(battery)
 	return ..()
 
 /obj/item/computer_hardware/battery_module/proc/charge_to_full()

code/modules/projectiles/guns/launcher/bows.dm

@@ -154,7 +154,7 @@
 
 /obj/item/gun/launcher/crossbow/bow/hardlight/unload(mob/user)
 	if(istype(bolt, /obj/item/arrow/energy))	// Let's not delete a Real Arrow^tm
-		qdel_null(bolt)
+		QDEL_NULL(bolt)
 		update_icon()
 	else
 		. = ..()