Skip incompatible with contrail neutron tests

Skip incompatible with contrail env neutron tests due to contrail
restrictions:
* Update of gateway is not supported.
https://bugs.launchpad.net/juniperopenstack/+bug/1466737
* Contrail backend don't allow removing of fixed ip from a port.
https://bugs.launchpad.net/juniperopenstack/+bug/1364677

Change-Id: I3ce0827f4cd154556a028fbaa932a0d031343257
Related-PROD: PROD-22168
diff --git a/tempest/api/network/test_networks.py b/tempest/api/network/test_networks.py
index 7345fd1..f727f02 100644
--- a/tempest/api/network/test_networks.py
+++ b/tempest/api/network/test_networks.py
@@ -310,6 +310,9 @@
     def test_create_delete_subnet_with_dhcp_enabled(self):
         self._create_verify_delete_subnet(enable_dhcp=True)
 
+    @testtools.skipIf(getattr(CONF.service_available, 'contrail', False),
+                      "Update of gateway is not supported in case of"
+                      "Contrail")
     @decorators.idempotent_id('3d3852eb-3009-49ec-97ac-5ce83b73010a')
     def test_update_subnet_gw_dns_host_routes_dhcp(self):
         network = self.create_network()
diff --git a/tempest/api/network/test_ports.py b/tempest/api/network/test_ports.py
index 5168423..900cd41 100644
--- a/tempest/api/network/test_ports.py
+++ b/tempest/api/network/test_ports.py
@@ -291,6 +291,9 @@
         for port in ports:
             self.assertEqual(sorted(fields), sorted(port.keys()))
 
+    @testtools.skipIf(getattr(CONF.service_available, 'contrail', False),
+                      "Contrail backend don't allow removing of fixed ip from "
+                      "a port.")
     @decorators.idempotent_id('63aeadd4-3b49-427f-a3b1-19ca81f06270')
     def test_create_update_port_with_second_ip(self):
         # Create a network with two subnets