Initializer skips prepare_dispatcher if Action Controller isn't in use. [#721 state:resolved]

railties/lib/initializer.rb

@@ -523,6 +523,7 @@ Run `rake gems:install` to install the missing gems.
     end
 
     def prepare_dispatcher
+      return unless configuration.frameworks.include?(:action_controller)
       require 'dispatcher' unless defined?(::Dispatcher)
       Dispatcher.define_dispatcher_callbacks(configuration.cache_classes)
       Dispatcher.new(RAILS_DEFAULT_LOGGER).send :run_callbacks, :prepare_dispatch