Opening two of the same wallet (tested in v0.18.0 of bitcoin-qt 64 bit) will cause a database collision, and will crash the program.

`[marshall@likon] {21:21} [~] $ bitcoin-0.18.0/bin/bitcoin-qt `
`terminate called after throwing an instance of 'std::runtime_error'  what():  BerkeleyBatch: Can't open database 8204388-wallet.dat (duplicates fileid 8b1c090000000800e25686350000000000000000 from 1352491-wallet.dat)`
`Aborted (core dumped)`

I have been able to reproduce the issue by importing two of the same wallet (with different filenames).
{
    
    if (!pwallet->GetBroadcastTransactions()) return false;
    
    if (isAbandoned()) return false;
    
    
    if (IsCoinBase()) return false;
    
    if (GetDepthInMainChain() != 0) return false;
    
    pwallet->WalletLogPrintf("Submitting wtx %s to mempool for relay\n", GetHash().ToString());
    
    
    
    
    
    
    
    
    
    bool ret = pwallet->chain().broadcastTransaction(tx, pwallet->m_default_max_tx_fee, relay, err_string);
    fInMempool |= ret;
    return ret;
}
std::set<uint256> CWalletTx::GetConflicts() const