[feature/controller] Check for proper status codes from controllers

PHPBB3-10864

tests/functional/fixtures/ext/foo/bar/config/routing.yml

@@ -9,3 +9,7 @@ foo_baz_controller:
 foo_template_controller:
     pattern: /foo/template
     defaults: { _controller: foo_bar.controller:template }
+
+foo_exception_controller:
+    pattern: /foo/foo_exception
+    defaults: { _controller: foo_bar.controller:exception }