Prevent AttributeError if no authorization

If you ask client if there is a service catalog when it is unauthorized
it tries to look up the service catalog on a None object. If the client
is unauthorized it should always return False as there cannot be a
service catalog.

Change-Id: I439f71e548b8230e7ce38d1a0e9d0d8f9b205d77
Closes-Bug: 1239219
Merge "Prevent AttributeError if no authorization"