private void dispatchVisitEnqueued() {
        try {
            while (dispatchFirstVisit());
        }
        catch (Exception e) {
            log.log(WARNING, "Uncaught exception in /document/v1 dispatch thread", e);
        }
    }
Dispatches enqueued requests until one is blocked.
vespaclient-container-plugin/src/main/java/com/yahoo/document/restapi/resource/DocumentV1ApiHandler.java