Reported here: https://github.com/bitcoin/bitcoin/pull/10244#issuecomment-378035305

Travis log here: https://travis-ci.org/bitcoin/bitcoin/jobs/361243719#L2810

Note the JSON exception:

```
test_framework.authproxy.JSONRPCException: The mempool was not loaded yet (-1) 
```

That exception was introduced here: https://github.com/bitcoin/bitcoin/commit/cb1e319fe9e198c9c5cf5236fe9af5a3d748b9e8#diff-a0c8f511d90e83aa9b5857e819ced344R1617

cc @jtimon 
{
    const CTransaction& tx = *ptx;
    const uint256 hash = tx.GetHash();
    AssertLockHeld(cs_main);
    LOCK(pool.cs); 
    if (pfMissingInputs) {
        *pfMissingInputs = false;
    }
    if (!CheckTransaction(tx, state))
        return false; 
    
    if (tx.IsCoinBase())
        return state.DoS(100, false, REJECT_INVALID, "coinbase");
    
    std::string reason;
    if (fRequireStandard && !IsStandardTx(tx, reason))
        return state.DoS(0, false, REJECT_NONSTANDARD, reason);
    
    
    
    if (::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) < MIN_STANDARD_TX_NONWITNESS_SIZE)
        return state.DoS(0, false, REJECT_NONSTANDARD, "tx-size-small");
    
    
    
    if (!CheckFinalTx(tx, STANDARD_LOCKTIME_VERIFY_FLAGS))
        return state.DoS(0, false, REJECT_NONSTANDARD, "non-final");