A regression introduced in If03b166d3ecc3e7fa6b7f1a0c69f8ab1cc7b1972
causes a glance image with the type 'raw' in ceph to fail to CoW
clone which prevents launching at all in this case.
The original patch did not update imagebackend.py [1] to use the new
nova.objects.ImageMeta object so the clone() function passes a normal
dict to the is_cloneable() function.
Additionally add another test to ensure that not passing disk_format
will fail, but not result in an exception. It will simply mean that
the function returns that it cannot take advantage of the CoW cloning
ceph provides.
[1] f2e2a5891d/nova/virt/libvirt/imagebackend.py (L824)
Change-Id: I7ae107bfccab7ff66c09d96856722dd6e60fdd96
Closes-Bug: #1508230
(cherry picked from commit 835ff1bf73)
474e7bb3f3