@Override
 protected StoredBlock addToBlockStore(StoredBlock storedPrev, Block block)
     throws BlockStoreException, VerificationException {
   StoredBlock newBlock = storedPrev.build(block);
   blockStore.put(
       newBlock, new StoredUndoableBlock(newBlock.getHeader().getHash(), block.transactions));
   return newBlock;
 }
 @Override
 protected StoredBlock addToBlockStore(
     StoredBlock storedPrev, Block header, TransactionOutputChanges txOutChanges)
     throws BlockStoreException, VerificationException {
   StoredBlock newBlock = storedPrev.build(header);
   blockStore.put(newBlock, new StoredUndoableBlock(newBlock.getHeader().getHash(), txOutChanges));
   return newBlock;
 }