Add OldElementsController base class

app/controllers/old_elements_controller.rb

@@ -0,0 +1,19 @@
+class OldElementsController < ApplicationController
+  layout :map_layout
+
+  before_action :authorize_web
+  before_action :set_locale
+  before_action -> { check_database_readable(:need_api => true) }
+  before_action :require_oauth
+
+  authorize_resource
+
+  before_action :require_moderator_for_unredacted_history
+  around_action :web_timeout
+
+  private
+
+  def require_moderator_for_unredacted_history
+    deny_access(nil) if params[:show_redactions] && !current_user&.moderator?
+  end
+end