[NO ISSUE][STO] Fix opening of inverted index deleted keys cursor

- user model changes: no
- storage format changes: no
- interface changes: no

Details:
- LSMInvertedIndexDeletedKeysBTreeMergeCursor.open used to open
  their inner cursors twice. This change fixes it so they are open
  only once.

Change-Id: Ib325348265d8cc203aea6cd22591a49221f95411
Reviewed-on: https://asterix-gerrit.ics.uci.edu/2510
Reviewed-by: Luo Chen <cluo8@uci.edu>
Sonar-Qube: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Contrib: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
diff --git a/hyracks-fullstack/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexDeletedKeysBTreeMergeCursor.java b/hyracks-fullstack/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexDeletedKeysBTreeMergeCursor.java
index f1f5241..faa90eb 100644
--- a/hyracks-fullstack/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexDeletedKeysBTreeMergeCursor.java
+++ b/hyracks-fullstack/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexDeletedKeysBTreeMergeCursor.java
@@ -60,7 +60,6 @@
         ArrayList<IIndexAccessor> btreeAccessors = lsmInitialState.getDeletedKeysBTreeAccessors();
         for (int i = 0; i < numBTrees; i++) {
             rangeCursors[i] = btreeAccessors.get(i).createSearchCursor(false);
-            btreeAccessors.get(i).search(rangeCursors[i], btreePredicate);
         }
         IndexCursorUtils.open(btreeAccessors, rangeCursors, btreePredicate);
         try {