@Override
    public Iterator<HardDeleteInfo> getHardDeleteMessages(MessageReadSet readSet, StoreKeyFactory factory,
        List<byte[]> recoveryInfoList) {
      throw new UnsupportedOperationException();
    }
A mock implementation of {@link MessageStoreHardDelete} that can be set to return {@link MessageInfo} for a
particular {@link MockId}.
ambry-store/src/test/java/com/github/ambry/store/BlobStoreTest.java