BGP router now handles the case where groups don't exists right away.

Also reworked some logic to make delete routes work.

Change-Id: I1f65279284b85144a847f1295fcbd7695cb59167
diff --git a/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleStatisticStore.java b/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleStatisticStore.java
index 492ab27..9cfa41d 100644
--- a/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleStatisticStore.java
+++ b/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleStatisticStore.java
@@ -154,8 +154,16 @@
 
     private ConnectPoint buildConnectPoint(FlowRule rule) {
         PortNumber port = getOutput(rule);
+
+        boolean hasGoto = rule.treatment().instructions()
+                .stream()
+                .anyMatch(i -> (i instanceof Instructions.GroupInstruction)
+                        || (i instanceof Instructions.TableTypeTransition));
+
         if (port == null) {
-            log.debug("Rule {} has no output.", rule);
+            if (!hasGoto) {
+                log.debug("Rule {} has no output.", rule);
+            }
             return null;
         }
         ConnectPoint cp = new ConnectPoint(rule.deviceId(), port);