Powervm driver failing on snapshot due to missing update_task_state call

[David Peraza]

snapshot now takes a new update_task_state function pointer, powervm driver needs to make the expected calls to support this otherwise snapshot fails with unexpected state errors.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/23249

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/23249
Committed: http://github.com/openstack/nova/commit/f54113e38dfd6b8e593789e3b195bdb7a78b1d3c
Submitter: Jenkins
Branch: master

commit f54113e38dfd6b8e593789e3b195bdb7a78b1d3c
Author: David Peraza <email address hidden>
Date: Thu Feb 28 13:07:10 2013 +0000

    Updating powervm driver snapshot with update_task_state flow

    Fixes bug 1136359

    Without this change snapshot still works but instance task state
    does not get updated correctly and nova logs will show expected
    task state erros from compute manager.

    Also added a snapshot test.

    Change-Id: I0f4ed24aa82a66fafc4b6813d017618ae07b4751