Previously, we were storing the WSGI-style UTF-8-bytes-decoded-as-Latin-1
strings in the JSON field, and sending them back to eventlet directly.
If running in a mixed py2/py3 cluster, replication would eventually get
that back to the py2 server, and worse, the native-string version would
get back to the py3 server! Then on GET or HEAD, eventlet would barf
if any characters were outside the Latin-1 range.
Closes-Bug: #1837805
Change-Id: I31d942e72fd7bfbb1db4dbb1dd522dff69969e5d
71f83963c2