stop using __send__ and just module eval in the extensions

actionpack/lib/action_dispatch/routing/route_set.rb

@@ -124,9 +124,8 @@ def length
         end
 
         def install(destinations = [ActionController::Base, ActionView::Base])
-          destinations.each do |dest|
-            dest.__send__(:include, @module)
-          end
+          helper = @module
+          destinations.each { |d| d.module_eval { include helper } }
         end
 
         private