basho/riak_kv — pull request #588 by engelsanchez (2013-06-25 15:54:43+00:00)
Title: Multi backend was missing data_size function

It could report size as a capability if all backends had it (bitcask and
level both do) but there was no data_size method! So it would crash on
handoff.

/cc @jrwest

You can verify this with the verify_build_cluster riak_test with and without the multi backend