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 
if (gArgs.GetBoolArg("-peerbloomfilters", DEFAULT_PEERBLOOMFILTERS))
        nLocalServices = ServiceFlags(nLocalServices | NODE_BLOOM);
    if (gArgs.GetArg("-rpcserialversion", DEFAULT_RPC_SERIALIZE_VERSION) < 0)
        return InitError("rpcserialversion must be non-negative.");
    if (gArgs.GetArg("-rpcserialversion", DEFAULT_RPC_SERIALIZE_VERSION) > 1)
        return InitError("unknown rpcserialversion requested.");
    nMaxTipAge = gArgs.GetArg("-maxtipage", DEFAULT_MAX_TIP_AGE);
    fEnableReplacement = gArgs.GetBoolArg("-mempoolreplacement", DEFAULT_ENABLE_REPLACEMENT);
    if ((!fEnableReplacement) && gArgs.IsArgSet("-mempoolreplacement")) {
        
        std::string strReplacementModeList = gArgs.GetArg("-mempoolreplacement", "");  
        std::vector<std::string> vstrReplacementModes;
        boost::split(vstrReplacementModes, strReplacementModeList, boost::is_any_of(","));
        fEnableReplacement = (std::find(vstrReplacementModes.begin(), vstrReplacementModes.end(), "fee") != vstrReplacementModes.end());
    }
    return true;
}
static bool LockDataDirectory(bool probeOnly)
{
    
    fs::path datadir = GetDataDir();
    if (!DirIsWritable(datadir)) {
        return InitError(strprintf(_("Cannot write to data directory '%s'; check permissions."), datadir.string()));
    }
    if (!LockDirectory(datadir, ".lock", probeOnly)) {
        return InitError(strprintf(_("Cannot obtain a lock on data directory %s. %s is probably already running."), datadir.string(), _(PACKAGE_NAME)));
    }
    return true;
}
bool AppInitSanityChecks()