trigger_transition doesn't inherit from base trigger

fgd/brush/trigger/trigger_transition.fgd

@@ -1,5 +1,5 @@
 @SolidClass 
-	base(Trigger, Origin) 
+	base(BaseEntityBrush, Origin) 
 = trigger_transition: "A volume that's used to control which entities go through the level transition. " +
 	"Create one or more trigger_transitions and give them the same name as the changelevel landmark. " +
 	"Any entities within the trigger_transition(s) will go to the next map. " +