Endpoint-less Services keep the lbaasspec handler endlessly retrying

When you define a Service without a selector, Kubernetes does not create an endpoints object for it.

    kind: Service
    apiVersion: v1
    metadata:
      name: kuryr-svc-router
      namespace: kube-system
    spec:
      type: ClusterIP
      clusterIP: 172.30.255.254
      ports:
        - protocol: TCP
          port: 80

This ends up in the LBaaSSpecHandler failing to set up the lbaas spec on the endpoint object:

    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging Traceback (most recent call last):
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/opt/stack/kuryr-kubernetes/kuryr_kubernetes/handlers/logging.py", line 37, in __call__
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging self._handler(event)
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/opt/stack/kuryr-kubernetes/kuryr_kubernetes/handlers/retry.py", line 66, in __call__
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging ex.reraise = False
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 220, in __exit__
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging self.force_reraise()
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 196, in force_reraise
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging six.reraise(self.type_, self.value, self.tb)
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/opt/stack/kuryr-kubernetes/kuryr_kubernetes/handlers/retry.py", line 61, in __call__
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging self._handler(event)
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/opt/stack/kuryr-kubernetes/kuryr_kubernetes/handlers/k8s_base.py", line 63, in __call__
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging self.on_present(obj)
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/opt/stack/kuryr-kubernetes/kuryr_kubernetes/controller/handlers/lbaas.py", line 49, in on_present
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging self._set_lbaas_spec(service, lbaas_spec)
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging File "/opt/stack/kuryr-kubernetes/kuryr_kubernetes/controller/handlers/lbaas.py", line 165, in _set_lbaas_spec
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging raise k_exc.ResourceNotReady(ep_link)
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging ResourceNotReady: Resource not ready: u'/api/v1/namespaces/kube-system/endpoints/kuryr-svc-router'
    Jun 14 13:09:49 gerrit-472763vm-0 python[2454]: 2017-06-14 13:09:49.382 2454 ERROR kuryr_kubernetes.handlers.logging
    Jun 14 13:18:24 gerrit-472763vm-0 python[2454]: 2017-06-14 13:18:24.855 2454 ERROR kuryr_kubernetes.handlers.logging [-] Failed to handle event {u'object': {u'status': {u'loadBalancer': {}}, u'kind': u'Service', u'spec': {u'clusterIP': u'172.30.255.254', u'type': u'ClusterIP', u'ports': [{u'targetPort': 80, u'protocol': u'TCP', u'port': 80}], u'sessionAffinity': u'None'}, u'apiVersion': u'v1', u'metadata': {u'name': u'kuryr-svc-router', u'namespace': u'kube-system', u'resourceVersion': u'42', u'creationTimestamp': u'2017-06-14T10:30:33Z', u'selfLink': u'/api/v1/namespaces/kube-system/services/kuryr-svc-router', u'uid': u'7f2ee8a3-50ec-11e7-9fdb-fa163e55148f'}}, u'type': u'ADDED'}: ResourceNotReady: Resource not ready: u'/api/v1/namespaces/kube-system/endpoints/kuryr-svc-router

We should probably treat selector-less services differently or maybe use Third Party Resources (TPR).