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 
{
    int nCheckLevel = gArgs.GetArg("-checklevel", DEFAULT_CHECKLEVEL);
    int nCheckDepth = gArgs.GetArg("-checkblocks", DEFAULT_CHECKBLOCKS);
    if (request.fHelp || request.params.size() > 2)
        throw std::runtime_error(
            RPCHelpMan{"verifychain",
                "\nVerifies blockchain database.\n",
                {
                    {"checklevel", RPCArg::Type::NUM,  strprintf("%d, range=0-4", nCheckLevel), "How thorough the block verification is."},
                    {"nblocks", RPCArg::Type::NUM,  strprintf("%d, 0=all", nCheckDepth), "The number of blocks to check."},
                },
                RPCResult{
            "true|false       (boolean) Verified or not\n"
                },
                RPCExamples{
                    HelpExampleCli("verifychain", "")
            + HelpExampleRpc("verifychain", "")
                },
            }.ToString());
    LOCK(cs_main);
    if (!request.params[0].isNull())
        nCheckLevel = request.params[0].get_int();
    if (!request.params[1].isNull())
        nCheckDepth = request.params[1].get_int();
    return CVerifyDB().VerifyDB(Params(), pcoinsTip.get(), nCheckLevel, nCheckDepth);
}
static UniValue SoftForkMajorityDesc(int version, const CBlockIndex* pindex, const Consensus::Params& consensusParams)