Evacuated instance disk not deleted for non shared storage

[Kravchenko Pavel]

After instance evacuated from failed host and cleaned up during host boot in nova.compute/manager._destroy_evacuated_instances, the instance is removed but it's disk files are always kept in the filesystem.
In case of shared storage it is correct behavior, but in case of non shared storage the disks should be removed.
They not just consuming storage but also prevent from instance to be migrated back to the host in case of need.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/24600

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/24724

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/24600
Committed: http://github.com/openstack/nova/commit/52f6981aa35e27c48587ad2320891db8364edd02
Submitter: Jenkins
Branch: master

commit 52f6981aa35e27c48587ad2320891db8364edd02
Author: Kravchenko Pavel <email address hidden>
Date: Tue Apr 9 10:57:53 2013 +0300

    Evacuated instance disk not deleted

    Adds disk cleanup in case instance is not on shared storage.
    Added new methods to compute.rpc and virt.driver interface to validate
    that instance files located on shared storage on remote compute node.

    Fixes bug 1156269

    Change-Id: Ia4cc601d0d824ba04f595df96461cfa85ad3b90c

[Vish Ishaya (vishvananda)]

I don't think we can do a straight backport of this, it will need to done without rpc api changes if we want it in grizzly