use DVRMacAddressNotFound exception from neutron-lib

Commit I88e1aa2acf22389f69cb7d5704c80a5eb72a9bbe rehomed the
DVRMacAddressNotFound to neutron-lib. This patch consumes it by using
lib's version and removing neutron's version.

NeutronLibImpact

Change-Id: I70d1244c3bbf7664e15534e90a9d9b47e9c6e2f1

neutron/db/dvr_mac_db.py

@@ -21,6 +21,7 @@ from neutron_lib.callbacks import registry
 from neutron_lib.callbacks import resources
 from neutron_lib import constants
 from neutron_lib import exceptions as n_exc
+from neutron_lib.exceptions import dvr as dvr_exc
 from neutron_lib.objects import exceptions
 from neutron_lib.plugins import directory
 from neutron_lib.utils import net
@@ -81,7 +82,7 @@ class DVRDbMixin(ext_dvr.DVRMacAddressPluginBase):
     def _get_dvr_mac_address_by_host(self, context, host):
         dvr_obj = router.DVRMacAddress.get_object(context, host=host)
         if not dvr_obj:
-            raise ext_dvr.DVRMacAddressNotFound(host=host)
+            raise dvr_exc.DVRMacAddressNotFound(host=host)
         return self._make_dvr_mac_address_dict(dvr_obj)
 
     @utils.transaction_guard
@@ -126,7 +127,7 @@ class DVRDbMixin(ext_dvr.DVRMacAddressPluginBase):
 
         try:
             return self._get_dvr_mac_address_by_host(context, host)
-        except ext_dvr.DVRMacAddressNotFound:
+        except dvr_exc.DVRMacAddressNotFound:
             return self._create_dvr_mac_address(context, host)
 
     def _make_dvr_mac_address_dict(self, dvr_mac_entry, fields=None):

neutron/extensions/dvr.py

@@ -16,17 +16,8 @@ import abc
 
 from neutron_lib.api.definitions import dvr as apidef
 from neutron_lib.api import extensions
-from neutron_lib import exceptions
 import six
 
-from neutron._i18n import _
-
-
-# TODO(boden): consume with I88e1aa2acf22389f69cb7d5704c80a5eb72a9bbe
-class DVRMacAddressNotFound(exceptions.NotFound):
-    message = _("Distributed Virtual Router Mac Address for "
-                "host %(host)s does not exist.")
-
 
 class Dvr(extensions.APIExtensionDescriptor):
     """Extension class supporting distributed virtual router."""

neutron/tests/unit/db/test_dvr_mac_db.py

@@ -21,11 +21,11 @@ from neutron_lib.callbacks import resources
 from neutron_lib import constants
 from neutron_lib import context
 from neutron_lib import exceptions as lib_exc
+from neutron_lib.exceptions import dvr as dvr_exc
 from neutron_lib.plugins import directory
 from neutron_lib.utils import net
 
 from neutron.db import dvr_mac_db
-from neutron.extensions import dvr
 from neutron.objects import router
 from neutron.tests import tools
 from neutron.tests.unit.plugins.ml2 import test_plugin
@@ -57,7 +57,7 @@ class DvrDbMixinTestCase(test_plugin.Ml2PluginV2TestCase):
         self.assertEqual(entry.to_dict(), result)
 
     def test__get_dvr_mac_address_by_host_not_found(self):
-        self.assertRaises(dvr.DVRMacAddressNotFound,
+        self.assertRaises(dvr_exc.DVRMacAddressNotFound,
                           self.mixin._get_dvr_mac_address_by_host,
                           self.ctx, 'foo_host')