Remove case statement changes from 2e0840dd and 56ac32ad. Inheritance FTW.

activerecord/lib/active_record/relation/query_methods.rb

@@ -307,7 +307,7 @@ def reverse_sql_order(order_query)
 
       order_query.map do |o|
         case o
-        when Arel::Nodes::Ascending, Arel::Nodes::Descending
+        when Arel::Nodes::Ordering
           o.reverse
         when String, Symbol
           o.to_s.split(',').collect do |s|