private void fetchRecordsInto(List<ConsumerRecord<byte[], byte[]>> allFetchedRecords) {
        Map<TopicPartition, List<ConsumerRecord<byte[], byte[]>>> fetchedRecords = fetchRecords();
        fetchedRecords.values().forEach(allFetchedRecords::addAll);
    }
Supplies parameters to {@link #testHandleFetchResponseError(Errors, long, boolean, boolean)}.
clients/src/test/java/org/apache/kafka/clients/consumer/internals/FetcherTest.java