Fix Xmas barricade decorator not working (#5270)

# About the pull request

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Decorator changed the main icon of barricades. Not only this is bad due
to the file not being up to date, but also wiring doesn't care and
reuses the builtin icon file.

# Explain why it's good for the game
Event code not working

# Testing Photographs and Procedure
Spawn in, test


# Changelog
:cl:
fix: Fixed X-mas barricade wiring not applying properly.
/:cl:

---------

Co-authored-by: Drathek <[email protected]>

code/game/objects/structures/barricade/barricade.dm

@@ -19,6 +19,7 @@
 	var/force_level_absorption = 5 //How much force an item needs to even damage it at all.
 	var/barricade_hitsound
 	var/barricade_type = "barricade" //"metal", "plasteel", etc.
+	var/wire_icon = 'icons/obj/structures/barricades.dmi' //! Icon file used for the wiring
 	var/can_change_dmg_state = TRUE
 	var/damage_state = BARRICADE_DMG_NONE
 	var/closed = FALSE
@@ -102,9 +103,9 @@
 
 	if(is_wired)
 		if(!closed)
-			overlays += image('icons/obj/structures/barricades.dmi', icon_state = "[src.barricade_type]_wire")
+			overlays += image(wire_icon, icon_state = "[barricade_type]_wire")
 		else
-			overlays += image('icons/obj/structures/barricades.dmi', icon_state = "[src.barricade_type]_closed_wire")
+			overlays += image(wire_icon, icon_state = "[barricade_type]_closed_wire")
 
 	..()
 

code/modules/decorators/christmas.dm

@@ -66,7 +66,7 @@
 /datum/decorator/christmas/barricade/decorate(obj/structure/barricade/barricade)
 	if(!istype(barricade))
 		return
-	barricade.icon = 'icons/obj/structures/barricades_christmas.dmi'
+	barricade.wire_icon = 'icons/obj/structures/barricades_christmas.dmi'
 	barricade.update_icon()