This is the thorny thing about going the simpler route (in terms of message definitions) that I did. In an ideal world, `riak_pb_kv_codec` would handle its own bucket properties and decoding, and `riak_pb_search_codec` would do the same, u.s.w. However, that design would really require a whole bunch of machinery to manage who-decodes-what and creating message extensions and things that seemed overkill just for the framing layer. Perhaps there's a design that avoids this explicit call that I'm not seeing, but I just wanted to keep it simple.