presto-main/src/main/java/io/prestosql/operator/aggregation/arrayagg/LegacyArrayAggregationGroupState.java/LegacyArrayAggregationGroupState/forEach
class LegacyArrayAggregationGroupState:    @Override
    public void forEach(ArrayAggregationStateConsumer consumer)
    {
        BlockBuilder blockBuilder = blockBuilders.get(getGroupId());
        if (blockBuilder == null) {
            return;
        }

        for (int i = 0; i < blockBuilder.getPositionCount(); i++) {
            consumer.accept(blockBuilder, i);
        }
    }