Create separate middleware stack for initializer

railties/lib/rails/configuration.rb

@@ -108,10 +108,9 @@ def framework_root_path
       defined?(::RAILS_FRAMEWORK_ROOT) ? ::RAILS_FRAMEWORK_ROOT : "#{root_path}/vendor/rails"
     end
 
-    # TODO: Fix this when there is an application object
     def middleware
-      require 'action_controller'
-      ActionController::Dispatcher.middleware
+      require 'action_dispatch'
+      @middleware ||= ActionDispatch::MiddlewareStack.new
     end
 
     # Loads and returns the contents of the #database_configuration_file. The

railties/lib/rails/initializer.rb

@@ -608,6 +608,7 @@ def self.run(initializer = nil, config = nil)
 
   Initializer.default.add :build_application do
     if configuration.frameworks.include?(:action_controller)
+      ActionController::Dispatcher.middleware = configuration.middleware
       Rails.application = Rails::Application.new
     end
   end

railties/test/fcgi_dispatcher_test.rb

@@ -5,8 +5,6 @@
 require 'action_controller'
 require 'rails/fcgi_handler'
 
-Dispatcher.middleware.clear
-
 class RailsFCGIHandlerTest < Test::Unit::TestCase
   def setup
     @log = StringIO.new