Revert "no need delete endpoint explicitly in endpoint controller"

pkg/controller/endpoint/endpoints_controller.go

@@ -394,7 +394,15 @@ func (e *EndpointController) syncService(key string) error {
 	}
 	service, err := e.serviceLister.Services(namespace).Get(name)
 	if err != nil {
-		// Service has been deleted. So no need to do any more operations.
+		// Delete the corresponding endpoint, as the service has been deleted.
+		// TODO: Please note that this will delete an endpoint when a
+		// service is deleted. However, if we're down at the time when
+		// the service is deleted, we will miss that deletion, so this
+		// doesn't completely solve the problem. See #6877.
+		err = e.client.CoreV1().Endpoints(namespace).Delete(name, nil)
+		if err != nil && !errors.IsNotFound(err) {
+			return err
+		}
 		return nil
 	}