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 
template<typename T, typename Tk, typename... Args>
static inline bool SetHasKeys(const std::set<T>& set, const Tk& key, const Args&... args)
{
    return (set.count(key) != 0) || SetHasKeys(set, args...);
}
static constexpr size_t PER_UTXO_OVERHEAD = sizeof(COutPoint) + sizeof(uint32_t) + sizeof(bool);
static UniValue getblockstats(const JSONRPCRequest& request)