find_filter_prepend_position

# File actionpack/lib/action_controller/filters.rb, line 541
        def find_filter_prepend_position(filters, filter_type)
          # prepending a before or around filter puts it at the front of the call chain
          # after filters go before the first after filter in the chain
          if filter_type == :after
            filter_chain.each_with_index do |f,i|
              return i if f.after?
            end
            return -1
          end
          return 0
        end