There's an unfortunately common deployment config issue where the
per-service version discovery document doesn't return scheme and netloc
properly. (Especially common with glance, as there was an actually
upstream bug in the version discovery documents until very recently)
Since up until now nobody has actually been doing version discovery
(all of the python-client libs skip it and cheat by appending strings
to URLs locally) it's a pervassive issue with existing clouds.
The workaround is to grab the scheme and netloc from the catalog url,
since the service_url is a resource on the endpoint described by the
catalog_url, and since the catalog_url has to be correct or else nothing
works. Do this in the url normalization so that it persists in the
cache, and so that things like endpoint_override are not affected.
The need for the workaround and the description of it are documented in
the API-SIG spec on consuming version discovery.
Needed-By: I78019717cdee79cab43b0d11e737327aa281fd03
Change-Id: I29102e08998b662db8136bee32217532a316f263
8b8ff830e8