@Override
        protected KeyValueHeap newKVHeap(List<? extends KeyValueScanner> scanners,
          CellComparator comparator) throws IOException {
          return new MyKeyValueHeap(scanners, comparator, recordBlockSizeCallCount -> {
            if (recordBlockSizeCallCount == 6) {
              try {
                flushStore(store, id++);
              } catch (IOException e) {
                throw new RuntimeException(e);
              }
            }
          });
        }
Test for HBASE-3492 - Test split on empty colfam (no store files).
@throws IOException When the IO operations fail.
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStore.java