code: static Throwing.Runnable runEnhancer() {
      return () -> {
        Set<String> packages = PKG.getAndSet(null);
        if (packages != null) {
          EbeanEnhancer.newEnhancer().run(packages);
        }
      };
    }
docs: package for test.
  
  @return An enhancer task. It runs once per classloader instance.