use router az api def from neutron-lib

The route availability zone extension's API definition was rehomed into
neutron-lib with commit I8bc54b581c26d8472e38efaaa63741785e07d2b8
This patch consumes the API definition by:

- Removing the rehomed code from neutron.
- Using the APIExtensionDescriptor for the extension classes parent
thereby leveraging the values from the API defintion.
- Updating any references to now use the neutron-lib code.

NeutronLibImpact

Change-Id: I70db0cebe7656fde6ff1fe724fe604eb70e26f75

neutron/extensions/router_availability_zone.py

@@ -14,49 +14,15 @@
 
 import abc
 
-from neutron_lib.api.definitions import availability_zone as az_def
+from neutron_lib.api.definitions import router_availability_zone as apidef
 from neutron_lib.api import extensions
 import six
 
 
-EXTENDED_ATTRIBUTES_2_0 = {
-    'routers': {
-        az_def.COLLECTION_NAME: {'allow_post': False, 'allow_put': False,
-                                 'is_visible': True},
-        az_def.AZ_HINTS: {
-                'allow_post': True, 'allow_put': False, 'is_visible': True,
-                'validate': {'type:availability_zone_hint_list': None},
-                'default': []}}
-}
-
-
-class Router_availability_zone(extensions.ExtensionDescriptor):
+class Router_availability_zone(extensions.APIExtensionDescriptor):
     """Router availability zone extension."""
 
-    @classmethod
-    def get_name(cls):
-        return "Router Availability Zone"
-
-    @classmethod
-    def get_alias(cls):
-        return "router_availability_zone"
-
-    @classmethod
-    def get_description(cls):
-        return "Availability zone support for router."
-
-    @classmethod
-    def get_updated(cls):
-        return "2015-01-01T10:00:00-00:00"
-
-    def get_required_extensions(self):
-        return ["router", "availability_zone"]
-
-    def get_extended_resources(self, version):
-        if version == "2.0":
-            return EXTENDED_ATTRIBUTES_2_0
-        else:
-            return {}
+    api_definition = apidef
 
 
 @six.add_metaclass(abc.ABCMeta)

neutron/tests/unit/extensions/test_router_availability_zone.py

@@ -13,6 +13,7 @@
 
 import copy
 
+from neutron_lib.api.definitions import router_availability_zone as raz_apidef
 from neutron_lib.plugins import constants
 
 from neutron.db.availability_zone import router as router_az_db
@@ -20,7 +21,6 @@ from neutron.db import common_db_mixin
 from neutron.db import l3_agentschedulers_db
 from neutron.db import l3_db
 from neutron.extensions import l3
-from neutron.extensions import router_availability_zone as router_az
 from neutron.tests.unit.extensions import test_availability_zone as test_az
 from neutron.tests.unit.extensions import test_l3
 
@@ -57,7 +57,7 @@ class TestAZRouterCase(test_az.AZTestCommon, test_l3.L3NatTestCaseMixin):
 
         self._backup()
         l3.RESOURCE_ATTRIBUTE_MAP['routers'].update(
-            router_az.EXTENDED_ATTRIBUTES_2_0['routers'])
+            raz_apidef.RESOURCE_ATTRIBUTE_MAP['routers'])
         ext_mgr = AZL3ExtensionManager()
         super(TestAZRouterCase, self).setUp(plugin=plugin, ext_mgr=ext_mgr,
                                             service_plugins=service_plugins)