qos: fix shared filter for policies

The filter was working in Liberty, but was broken in Mitaka when
the field became synthetic as part of RBAC enablement for the resource.

_get_collection already knows how to handle the filter on database
level, so we just need to register the filter to pass it deeper into
db_api.

Change-Id: I40657bd15d9bf1e2bc6b0224254c916c35391cd1
Closes-Bug: #1591222

neutron/objects/rbac_db.py

@@ -302,6 +302,7 @@ class RbacNeutronMetaclass(type):
         mcs.update_synthetic_fields(bases, dct)
         mcs.replace_class_methods_with_hooks(bases, dct)
         cls = type(name, (RbacNeutronDbObjectMixin,) + bases, dct)
+        cls.add_extra_filter_name('shared')
         mcs.subscribe_to_rbac_events(cls)
 
         return cls

neutron/tests/unit/objects/qos/test_policy.py

@@ -397,3 +397,22 @@ class QosPolicyDbObjectTestCase(test_base.BaseDbObjectTestCase,
         self.assertNotIn(rule_obj_dscp, policy_obj_v1_0.rules)
         #NOTE(mangelajo): we should not check .VERSION, since that's the
         #                 local version on the class definition
+
+    def test_filter_by_shared(self):
+        policy_obj = policy.QosPolicy(
+            self.context, name='shared-policy', shared=True)
+        policy_obj.create()
+
+        policy_obj = policy.QosPolicy(
+            self.context, name='private-policy', shared=False)
+        policy_obj.create()
+
+        shared_policies = policy.QosPolicy.get_objects(
+            self.context, shared=True)
+        self.assertEqual(1, len(shared_policies))
+        self.assertEqual('shared-policy', shared_policies[0].name)
+
+        private_policies = policy.QosPolicy.get_objects(
+            self.context, shared=False)
+        self.assertEqual(1, len(private_policies))
+        self.assertEqual('private-policy', private_policies[0].name)