ActionController的替换是什么:Base.relative_url_root?

I am porting a 2.x rails app to rails3; we'll call it foo-app. Foo-app is one section of a larger rails app and lives at main_rails_app.com/foo-app. Previously we just set up the following in our foo-app production config to ensure that our foo-app routes worked properly:I am porting a 2.x rails app to rails3; we'll c