https://travis-ci.org/github/bitcoin/bitcoin/jobs/679885530#L8791
return false;
                WalletBatch(GetDatabase()).WriteMasterKey(pMasterKey.first, pMasterKey.second);
                if (fWasLocked)
                    Lock();
                return true;
            }
        }
    }
    return false;
}
void CWallet::chainStateFlushed(const CBlockLocator& loc)
{
    WalletBatch batch(GetDatabase());
    batch.WriteBestBlock(loc);
}
void CWallet::SetMinVersion(enum WalletFeature nVersion, WalletBatch* batch_in)
{
    LOCK(cs_wallet);
    if (nWalletVersion >= nVersion)
        return;
    nWalletVersion = nVersion;
    {
        WalletBatch* batch = batch_in ? batch_in : new WalletBatch(GetDatabase());
        if (nWalletVersion > 40000)
            batch->WriteMinVersion(nWalletVersion);
        if (!batch_in)
            delete batch;
    }
}
std::set<uint256> CWallet::GetConflicts(const uint256& txid) const