[MIRROR] Firefighter tanks can now be equipped with atmos modsuits [MDB IGNORE] (#11512)

* Firefighter tank can now be equipped in the suit storage slot of atmos modsuits. (#64709)

* Firefighter tanks can now be equipped with atmos modsuits

* Update mod_theme.dm

Co-authored-by: Aerden <27950824+Aerden@users.noreply.github.com>
Co-authored-by: Gandalf <9026500+Gandalf2k15@users.noreply.github.com>

code/game/objects/items/tanks/watertank.dm

@@ -33,13 +33,13 @@
 	toggle_mister(user)
 
 /obj/item/watertank/item_action_slot_check(slot, mob/user)
-	if(slot == user.getBackSlot())
+	if(slot == user.getBackSlot() || slot == ITEM_SLOT_SUITSTORE)
 		return 1
 
 /obj/item/watertank/proc/toggle_mister(mob/living/user)
 	if(!istype(user))
 		return
-	if(user.get_item_by_slot(user.getBackSlot()) != src)
+	if(user.get_item_by_slot(user.getBackSlot()) != src && user.get_item_by_slot(ITEM_SLOT_SUITSTORE) != src)
 		to_chat(user, span_warning("The watertank must be worn properly to use!"))
 		return
 	if(user.incapacitated())

code/modules/mod/mod_theme.dm

@@ -153,6 +153,7 @@
 	max_heat_protection_temperature = FIRE_IMMUNITY_MAX_TEMP_PROTECT
 	slowdown_inactive = 1.5
 	slowdown_active = 1
+	allowed_suit_storage = list(/obj/item/flashlight, /obj/item/tank/internals, /obj/item/watertank/atmos)
 	skins = list(
 		"atmospheric" = list(
 			HELMET_LAYER = NECK_LAYER,