ONOS-5691 ONOS-5742 Fixing intent framework difficulties

- Refactoring AbstractAccumulator to use less blocking synchronization
- Fixing bug in AbstractAccumulator that could leave some items
  without firing
- Updated IntentStore for resubmitting pending operations

Change-Id: Iaf240da65e11ceb7d7d745cf4e25bfb8c26ed1eb
diff --git a/core/common/src/test/java/org/onosproject/store/trivial/SimpleIntentStore.java b/core/common/src/test/java/org/onosproject/store/trivial/SimpleIntentStore.java
index 41ce036..02d7eb2 100644
--- a/core/common/src/test/java/org/onosproject/store/trivial/SimpleIntentStore.java
+++ b/core/common/src/test/java/org/onosproject/store/trivial/SimpleIntentStore.java
@@ -195,6 +195,11 @@
     }
 
     @Override
+    public IntentData getPendingData(Key intentKey) {
+        return pending.get(intentKey);
+    }
+
+    @Override
     public Iterable<IntentData> getPendingData(boolean localOnly, long olderThan) {
         long older = System.nanoTime() - olderThan * 1_000_000; //convert ms to ns
         final SystemClockTimestamp time = new SystemClockTimestamp(older);