CoraidDriver: REST session validity not checked into get_volume_info

[Jean-Baptiste RANSY]

All methods (except create_volume) are calling the method '_get_volume_info' to obtain the volume information.
(create_volume doesn't do that because the volume doesn't yet exists)

Since bugfixes https://bugs.launchpad.net/cinder/+bug/1157242 the REST session is no more verified when '_get_volume_info' is called.
This means that if the REST session expires, the driver is not more usable.

1) We will fix the problem
2) We will improve the session handler to no longer need, in each method, to explicitly call self._login ()

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/25671

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/25671
Committed: http://github.com/openstack/cinder/commit/b78fb081ac1be228cecebff2a49131accfe4525c
Submitter: Jenkins
Branch: master

commit b78fb081ac1be228cecebff2a49131accfe4525c
Author: Larry Matter <email address hidden>
Date: Thu Mar 28 16:29:38 2013 -0700

    REST session validity not checked in get_volume_info

    The fix for bug 1157242 introduced a new bug in Coraid cinder driver
    _get_volume_info that the login session is not checked for
    validity/timeout. This change addressesthat issue for all
    methods in the CoraidRESTClient class.

    Fixes bug 1160459

    Change-Id: Ib2d7ebbf3ef8ec35071f51c6168eb9b3af9405e6