@Override
    public ExtendedCell getNextIndexedKey() {
      // Fake block boundaries by having index of next block change as we go through scan.
      return PrivateCellUtil
        .createFirstOnRow(CELL_WITH_VERSIONS[CELL_WITH_VERSIONS_BLOCK2_BOUNDARY]);
    }
A StoreScanner for our CELL_GRID above. Fakes the block transitions. Does counts of calls to
optimize and counts of when optimize actually did an optimize.
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreScanner.java