[placement] Move resource_class_cache into placement hierarchy

Since only placement uses the resource_class_cache, move it
into the placement hierarchy.

Change-Id: I837d4b691f94af0487a66dacf5ae563e4423f6a3

Author: cdent

nova/api/openstack/placement/objects/resource_provider.py

@@ -42,8 +42,8 @@
 from nova.api.openstack.placement.objects import consumer as consumer_obj
 from nova.api.openstack.placement.objects import project as project_obj
 from nova.api.openstack.placement.objects import user as user_obj
+from nova.api.openstack.placement import resource_class_cache as rc_cache
 from nova.db.sqlalchemy import api_models as models
-from nova.db.sqlalchemy import resource_class_cache as rc_cache
 from nova.i18n import _
 from nova import rc_fields
 

nova/db/sqlalchemy/resource_class_cache.py renamed to nova/api/openstack/placement/resource_class_cache.py

@@ -13,9 +13,6 @@
 from oslo_concurrency import lockutils
 import sqlalchemy as sa
 
-# TODO(cdent): This file and its location is problematic for placement
-# extraction but we probably want to switch to os-resource-classes (like
-# os-traits) instead of moving it?
 from nova.api.openstack.placement import db_api
 from nova.api.openstack.placement import exception
 from nova.db.sqlalchemy import api_models as models

nova/tests/functional/api/openstack/placement/db/test_resource_class_cache.py

@@ -16,7 +16,7 @@
 from oslo_utils import timeutils
 
 from nova.api.openstack.placement import exception
-from nova.db.sqlalchemy import resource_class_cache as rc_cache
+from nova.api.openstack.placement import resource_class_cache as rc_cache
 from nova import rc_fields as fields
 from nova.tests.functional.api.openstack.placement import base