@Override
  public void shipped() throws IOException {
    if (storeHeap != null) {
      storeHeap.shipped();
    }
    if (joinedHeap != null) {
      joinedHeap.shipped();
    }
  }
A mocked list implementation - discards all updates.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/RegionScannerImpl.java