Updated openstack/openstack
Project: openstack/cinder  e077c1faf83a6ad186ade9dcf5d411a5e7c05c75

Clarify InvalidInput exception when the size is missing

In the case where size is None, the exception message
'Volume size  must be an integer...' is misleading.

Change-Id: Ida34a84f8b3d156e3dca54de594c991b5ef73295