public ProducerIdsDelta getOrCreateProducerIdsDelta() {
        if (producerIdsDelta == null) {
            producerIdsDelta = new ProducerIdsDelta(image.producerIds());
        }
        return producerIdsDelta;
    }
A change to the broker metadata image.
metadata/src/main/java/org/apache/kafka/image/MetadataDelta.java