Unifies datum var definitions (#2237)

code/controllers/subsystem/garbage.dm

@@ -234,33 +234,7 @@ SUBSYSTEM_DEF(garbage)
 	else if(D.gc_destroyed == GC_CURRENTLY_BEING_QDELETED)
 		CRASH("[D.type] destroy proc was called multiple times, likely due to a qdel loop in the Destroy logic")
 
-// Default implementation of clean-up code.
-// This should be overridden to remove all references pointing to the object being destroyed.
-// Return the appropriate QDEL_HINT; in most cases this is QDEL_HINT_QUEUE.
-// TODO: Move this and all datum var definitions into code/datums/datum.dm
-/datum/proc/Destroy(force=FALSE)
-	tag = null
-	var/list/timers = active_timers
-	active_timers = null
-	for(var/thing in timers)
-		var/datum/timedevent/timer = thing
-		if (timer.spent)
-			continue
-		qdel(timer)
-	var/list/dc = datum_components
-	for(var/I in dc)
-		var/datum/component/C = I
-		C._RemoveNoSignal()
-		qdel(C)
-	if(dc)
-		dc.Cut()
-	return QDEL_HINT_QUEUE
-
-/datum/var/gc_destroyed //Time when this object was destroyed.
-
 #ifdef TESTING
-/datum/var/running_find_references
-/datum/var/last_find_references = 0
 
 /datum/verb/find_refs()
 	set category = "Debug"

code/controllers/subsystem/timer.dm

@@ -210,7 +210,6 @@ SUBSYSTEM_DEF(timer)
 	timer_id_dict |= SStimer.timer_id_dict
 	bucket_list |= SStimer.bucket_list
 
-/datum/var/list/active_timers
 /datum/timedevent
 	var/id
 	var/datum/callback/callBack