code: @Override
      protected MessageResolverStrategy configureMessageResolverStrategy() {
          final MessageResolverStrategy candidate = configuredMessageResolverStrategy();
          return candidate == null ? super.configureMessageResolverStrategy() : candidate;
      }
docs: /*
  (non-Javadoc)
  @see es.sandbox.ui.messages.spring.MessagesConfigurationSupport#configureMessageResolverStrategy()