refactor session store initializer

config/initializers/session_store.rb

@@ -29,8 +29,10 @@
 
 # Be sure to restart your server when you modify this file.
 
-if Rails.env.production?
+session_store = Rails.env.production? ? :cache_store : :cookie_store
-  OpenProject::Application.config.session_store ActionDispatch::Session::CacheStore
+
-else
+session_options = {
-  OpenProject::Application.config.session_store :cookie_store, :key => '_open_project_session'
+  :key    => '_open_project_session'
-end
+}
+
+OpenProject::Application.config.session_store session_store, session_options