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 
setOrphans.insert(item.second);
            setPrevs.insert(item.second->pprev);
        }
    }
    for (std::set<const CBlockIndex*>::iterator it = setOrphans.begin(); it != setOrphans.end(); ++it)
    {
        if (setPrevs.erase(*it) == 0) {
            setTips.insert(*it);
        }
    }
    
    setTips.insert(chainActive.Tip());
    
    UniValue res(UniValue::VARR);
    for (const CBlockIndex* block : setTips)
    {
        UniValue obj(UniValue::VOBJ);
        obj.pushKV("height", block->nHeight);
        obj.pushKV("hash", block->phashBlock->GetHex());
        const int branchLen = block->nHeight - chainActive.FindFork(block)->nHeight;
        obj.pushKV("branchlen", branchLen);
        std::string status;
        if (chainActive.Contains(block)) {
            
            status = "active";
        } else if (block->nStatus & BLOCK_FAILED_MASK) {
            
            status = "invalid";
        } else if (!block->HaveTxsDownloaded()) {