message: index: Use batch writing in coinstatsindex WriteBlock
diff: @@ -219,7 +219,10 @@ bool CoinStatsIndex::WriteBlock(const CBlock& block, const CBlockIndex* pindex)
  m_muhash.Finalize(out);
  value.second.muhash = out;
  - return m_db->Write(DBHeightKey(pindex->nHeight), value) && m_db->Write(DB_MUHASH, m_muhash);
  + CDBBatch batch(*m_db);
  + batch.Write(DBHeightKey(pindex->nHeight), value);
  + batch.Write(DB_MUHASH, m_muhash);
  + return m_db->WriteBatch(batch);
  }
  static bool CopyHeightIndexToHashIndex(CDBIterator& db_it, CDBBatch& batch,
  