Function make_net_span_tree 

pub fn make_net_span_tree(
    blocks: &[BlockMetadata],
    record_builder: &mut NetSpanRecordBuilder,
    blob_storage: Arc<BlobStorage>,
    stream: &StreamMetadata,
    process_id: Arc<String>,
    convert_ticks: ConvertTicks,
) -> impl Future<Output = Result<(), Error>>

Drives a NetSpanTreeBuilder across a contiguous group of net event blocks, stitching open spans across block boundaries.