Fix: enforce to remove security group rules

1. resolve a NPE caused by null subnet gateway

Change-Id: I48abe52d7fb508a53377dcbcc613eca446ccda4e
diff --git a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackRoutingFloatingIpHandler.java b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackRoutingFloatingIpHandler.java
index cbe22e0..60b924b 100644
--- a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackRoutingFloatingIpHandler.java
+++ b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackRoutingFloatingIpHandler.java
@@ -27,7 +27,6 @@
 import org.onlab.packet.IpAddress;
 import org.onlab.packet.MacAddress;
 import org.onlab.packet.VlanId;
-import org.onosproject.cfg.ComponentConfigService;
 import org.onosproject.cluster.ClusterService;
 import org.onosproject.cluster.LeadershipService;
 import org.onosproject.cluster.NodeId;
@@ -86,7 +85,6 @@
 import static org.onosproject.openstacknetworking.api.OpenstackNetworkEvent.Type.OPENSTACK_PORT_PRE_REMOVE;
 import static org.onosproject.openstacknetworking.util.OpenstackNetworkingUtil.associatedFloatingIp;
 import static org.onosproject.openstacknetworking.util.OpenstackNetworkingUtil.getGwByComputeDevId;
-import static org.onosproject.openstacknetworking.util.OpenstackNetworkingUtil.getPropertyValueAsBoolean;
 import static org.onosproject.openstacknetworking.util.OpenstackNetworkingUtil.isAssociatedWithVM;
 import static org.onosproject.openstacknetworking.util.OpenstackNetworkingUtil.swapStaleLocation;
 import static org.onosproject.openstacknetworking.util.RulePopulatorUtil.buildExtension;
@@ -103,8 +101,6 @@
     private static final String ERR_FLOW = "Failed set flows for floating IP %s: ";
     private static final String ERR_UNSUPPORTED_NET_TYPE = "Unsupported network type %s";
 
-    private static final String USE_SECURITY_GROUP = "useSecurityGroup";
-
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected CoreService coreService;
 
@@ -118,9 +114,6 @@
     protected ClusterService clusterService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected ComponentConfigService componentConfigService;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected OpenstackNodeService osNodeService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
@@ -886,21 +879,12 @@
                     NetFloatingIP fip =
                             associatedFloatingIp(instPort, osRouterAdminService.floatingIps());
 
-                    boolean sgFlag = getPropertyValueAsBoolean(
-                            componentConfigService.getProperties(
-                                    OpenstackSecurityGroupHandler.class.getName()),
-                            USE_SECURITY_GROUP);
-
                     if (fip != null) {
                         instancePortService.updateInstancePort(
                                             instPort.updateState(REMOVE_PENDING));
                         eventExecutor.execute(() -> updateFipStore(event.port().getId()));
                     } else {
-                        // FIXME: we have dependency with security group, need to
-                        // find a better way to remove this dependency
-                        if (!sgFlag) {
-                            instancePortService.removeInstancePort(instPort.portId());
-                        }
+                        instancePortService.removeInstancePort(instPort.portId());
                     }
                     break;
                 default: