tests for flow service

Change-Id: I7138c7642f266c0691ead13ff1f230d063eb6b71
diff --git a/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleFlowRuleStore.java b/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleFlowRuleStore.java
index 2f0de26..fbfd0ee 100644
--- a/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleFlowRuleStore.java
+++ b/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleFlowRuleStore.java
@@ -60,6 +60,7 @@
          *  find the rule and mark it for deletion.
          *  Ultimately a flow removed will come remove it.
          */
+
         if (flowEntries.containsEntry(did, rule)) {
             synchronized (flowEntries) {