Handle errors in pre_migrate and new style RPC migrations messages
Handle errors in pre_migrate and new style RPC migrations messages

Recently trunk changed from sending migration_id to migration causing
the previous code to not set the migration to error correctly.

Also, handle pre_migrate which creates the migration record so there
is no migration or migration_id to get from kwargs

sridevikoushik31/nova,sridevikoushik31/nova,sridevikoushik31/nova,sridevikoushik31/nova