public void copyOrdering(HitGroup hitGroup) {
        setOrderer(hitGroup.getOrderer());
        setDeletionBreaksOrdering(hitGroup.getDeletionBreaksOrdering());
        setOrdered(hitGroup.orderedHits);
    }
Sets sorting information to be the same as for the provided hitGroup.
The contained hits should already be sorted in the order specified by
the hitGroup given as argument.
container-search/src/main/java/com/yahoo/search/result/HitGroup.java