Fix to reinstall flow rules when they are missing in FlowRuleService.

Change-Id: I1e7e0d62e27012cd090f3a72eb92eadc85afafdf
(cherry picked from commit 5c7fe3acf43bf1304038a7be55a5fd45e5805396)
diff --git a/core/net/src/test/java/org/onosproject/net/flow/impl/FlowRuleManagerTest.java b/core/net/src/test/java/org/onosproject/net/flow/impl/FlowRuleManagerTest.java
index 3801388..300b023 100644
--- a/core/net/src/test/java/org/onosproject/net/flow/impl/FlowRuleManagerTest.java
+++ b/core/net/src/test/java/org/onosproject/net/flow/impl/FlowRuleManagerTest.java
@@ -207,7 +207,7 @@
         FlowRule rule = flowRule(hval, hval);
         service.applyFlowRules(rule);
 
-        assertNotNull("rule should be found", service.getFlowEntries(DID));
+        assertNotNull("rule should be found", service.getFlowEntry(rule));
         return rule;
     }
 
@@ -234,6 +234,24 @@
     }
 
     @Test
+    public void getFlowEntry() {
+        assertTrue("store should be empty",
+                Sets.newHashSet(service.getFlowEntries(DID)).isEmpty());
+        FlowRule f1 = addFlowRule(1);
+        FlowRule f2 = addFlowRule(2);
+
+        FlowEntry fe1 = new DefaultFlowEntry(f1);
+        FlowEntry fe2 = new DefaultFlowEntry(f2);
+        assertEquals("2 rules should exist", 2, flowCount());
+
+        FlowEntry actual1 = service.getFlowEntry(f1);
+        FlowEntry actual2 = service.getFlowEntry(f2);
+
+        assertEquals(fe1, actual1);
+        assertEquals(fe2, actual2);
+    }
+
+    @Test
     public void getFlowEntries() {
         assertTrue("store should be empty",
                    Sets.newHashSet(service.getFlowEntries(DID)).isEmpty());