Add Active Active L3 GW API test cases

Depends-On: I34e2453ab206c13c3ca40c4181970c320bdd8e67
Change-Id: I8ee8d40d5fa0dbb1c3bbfd4bac7d38e4b108a58b
diff --git a/neutron_tempest_plugin/api/base_routers.py b/neutron_tempest_plugin/api/base_routers.py
index 52db742..94db116 100644
--- a/neutron_tempest_plugin/api/base_routers.py
+++ b/neutron_tempest_plugin/api/base_routers.py
@@ -31,10 +31,10 @@
             pass
 
     def _create_router(self, name, admin_state_up=False,
-                       external_network_id=None, enable_snat=None):
+                       external_network_id=None, enable_snat=None, **kwargs):
         # associate a cleanup with created routers to avoid quota limits
         router = self.create_router(name, admin_state_up,
-                                    external_network_id, enable_snat)
+                                    external_network_id, enable_snat, **kwargs)
         self.addCleanup(self._cleanup_router, router)
         return router