Cannot retype the volume that was created from a snapshot.

Detailed bug description:
The volume created from a snapshot that was removed after creation of the volume cannot be migrated to another cinder backend.
Steps to reproduce:
Detailed way to reproduce this bug is in the attached file. Here is a short description:
1. install MOS with one controller/cinder node and another compute node
2. make two cinder LVM-based backends and create two cinder types appropriately
3. create a volume in the first backend
4. make a snapshot of this volume
5. make a volume fom the snapshot
6. delete the snapshot
7. try retyping the volume using "cinder retype" command
Expected results:
volume migrates to another backend
Actual result:
volume stays located on the original backend
2017-04-13 09:31:52.871 31680 ERROR oslo_messaging.rpc.dispatcher VolumeMigrationFailed: Volume migration failed: failed to create new_volume on destination host
Log file is attached
Workaround:
Don't know yet
Impact:
Volumes cannot be migrated to another backend
Description of the environment:
MOS 9.0
ii cinder-api 2:8.1.0-6~u14.04+mos14 all OpenStack block storage system - API server
ii cinder-backup 2:8.1.0-6~u14.04+mos14 all OpenStack block storage system - Backup server
ii cinder-common 2:8.1.0-6~u14.04+mos14 all OpenStack block storage system - common files
ii cinder-scheduler 2:8.1.0-6~u14.04+mos14 all OpenStack block storage system - Scheduler server
ii cinder-volume 2:8.1.0-6~u14.04+mos14 all OpenStack block storage system - Volume server
ii python-cinder 2:8.1.0-6~u14.04+mos14 all OpenStack block storage system - Python libraries
ii python-cinderclient 1:1.6.0-3~u14.04+mos4 all Python bindings to the OpenStack Volume API - Python 2.x

MOS 9.2
iU cinder-api 2:8.1.1-6~u14.04+mos25 all OpenStack block storage system - API server
iU cinder-backup 2:8.1.1-6~u14.04+mos25 all OpenStack block storage system - Backup server
iF cinder-common 2:8.1.1-6~u14.04+mos25 all OpenStack block storage system - common files
iU cinder-scheduler 2:8.1.1-6~u14.04+mos25 all OpenStack block storage system - Scheduler server
iU cinder-volume 2:8.1.1-6~u14.04+mos25 all OpenStack block storage system - Volume server
ii python-cinder 2:8.1.1-6~u14.04+mos25 all OpenStack block storage system - Python libraries
ii python-cinderclient 1:1.6.0-3~u14.04+mos4 all Python bindings to the OpenStack Volume API - Python 2.x

Additional information:
The cinder volume that was created from a snapshot has a snapshot ID set. When a snapshot is removed, this field is not updated. I think that this is the reason why I cannot migrate the volume using "cinder retype" operation from one cinder backend to another.