code: public final Object fe(Object... args) {
      if (GWT.getUncaughtExceptionHandler() != null) {
        try {
          return f(args);
        } catch (Exception e) {
          GWT.getUncaughtExceptionHandler().onUncaughtException(e);
        }
        return true;
      }
      return f(args);
    }
docs: Methods fe(...) should be used from asynchronous contexts so as we can
  catch the exception and send it to the GWT UncaughtExceptionHandler
  They are intentionally final to avoid override them.