Merge "Add migrate_volume to BaseVD"

diff --cc cinder/volume/driver.py
index 37ff9f90baac56dc34442a5f958d17663ee411e4,2b3f2a540e9c3c4d79160b2c70229bcb238f8e6b..917132629e395b4b9c9fd3424e2b766ed784ee6e
--- 1/cinder/volume/driver.py
--- 2/cinder/volume/driver.py
+++ b/cinder/volume/driver.py
@@@ -1392,14 -1392,18 +1392,22 @@@ class BaseVD(object)
          """Get provider info updates from driver.
  
          :param volumes: List of Cinder volumes to check for updates
 -        :return: dict of update {'id': uuid, provider_id: <provider-id>}
 +        :param snapshots: List of Cinder snapshots to check for updates
 +        :return: tuple (volume_updates, snapshot_updates)
 +
 +        where volume updates {'id': uuid, provider_id: <provider-id>}
 +        and snapshot updates {'id': uuid, provider_id: <provider-id>}
          """
 -        return None
 +        return None, None
  
+     def migrate_volume(self, context, volume, host):
+         """Migrate volume stub.
+ 
+         This is for drivers that don't implement an enhanced version
+         of this operation.
+         """
+         return (False, None)
+ 
  
  @six.add_metaclass(abc.ABCMeta)
  class LocalVD(object):