Fix Domain not found exception handling.

cloudcontrol/node/hypervisor/domains/vm_tags.py

@@ -28,7 +28,7 @@ def _vir_tag(func):
                 # sometimes, libvirt tells us too late when a domain is removed
                 # we just ignore the error and remove the domain
                 dom.hypervisor.domains.pop(dom.name)
-                dom.tag_db.remove_sub_object(dom.name)
+                dom.hypervisor.handler.tag_db.remove_sub_object(dom.name)
                 return
             logger.exception('Unexpected libvirt error')
             dom.hypervisor.handler.virt_connect_restart()