docs: public static List<List<OperatorStateHandle>> applyRepartitioner(
  		OperatorStateRepartitioner opStateRepartitioner,
  		List<List<OperatorStateHandle>> chainOpParallelStates,
  		int oldParallelism,
  		int newParallelism) {
  
  		if (chainOpParallelStates == null) {
  			return Collections.emptyList();
  		}
  
  		return opStateRepartitioner.repartitionState(
  			chainOpParallelStates,
  			oldParallelism,
  			newParallelism);
  		}