Fix logic in test_db_loadbalancer

[Eugene Nikanorov]

Several methods in test_db_loadbalancer have incorrect logic like the following piece of code:

res = self._create_vip(fmt,
                                       name,
                                       pool_id,
                                       protocol,
                                       protocol_port,
                                       admin_state_up,
                                       subnet_id=tmp_subnet['subnet']['id'],
                                       **kwargs)
vip = self.deserialize(fmt or self.fmt, res)
if res.status_int >= 400:
       raise webob.exc.HTTPClientError(code=res.status_int)

In case of res.status_int >= 400 code tries to deserialize malformed body and it throws an exception masking real cause of failure.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/29147

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/29147
Committed: http://github.com/openstack/quantum/commit/2648314b4cb884fe317e246fd418d2674fc0192e
Submitter: Jenkins
Branch: master

commit 2648314b4cb884fe317e246fd418d2674fc0192e
Author: Eugene Nikanorov <email address hidden>
Date: Wed May 15 01:14:30 2013 +0400

    Fix logic in test_db_loadbalancer

    Fix code to check HTTP error code before attempt to deserialize body

    fixes bug 1180113

    Change-Id: I1d75e0fe739dfa70ef415602e669319797af026f