When a pass of CreateTransaction fails to select enough bitcoin to meet the nFeeNeeded the next pass through may select a far smaller collection of inputs.  Currently it will continue to use the old fee amount based on the larger set of inputs, which can cause a non-trivial over-payment.

This may be the cause of the behavior reported here: https://www.reddit.com/r/Bitcoin/comments/5ltw5n/bitcoin_core_v0131_sends_enormously_high_fee/

Long ago fixing this was tricky due to a catch-22 between signing the transaction and knowing how much fee was required.  But after #9465 the whole algorithm will run using a dummy signature, so when there is already a change output fixing up the fee after finding a sufficient transaction should be a matter of a ~2 line change.

private:
    const CKeyStore &keystore;
    std::vector<CKeyID> &vKeys;
public:
    CAffectedKeysVisitor(const CKeyStore &keystoreIn, std::vector<CKeyID> &vKeysIn) : keystore(keystoreIn), vKeys(vKeysIn) {}
    void Process(const CScript &script) {
        txnouttype type;
        std::vector<CTxDestination> vDest;
        int nRequired;
        if (ExtractDestinations(script, type, vDest, nRequired)) {
            BOOST_FOREACH(const CTxDestination &dest, vDest)
                boost::apply_visitor(*this, dest);
        }
    }
    void operator()(const CKeyID &keyId) {
        if (keystore.HaveKey(keyId))
            vKeys.push_back(keyId);
    }
    void operator()(const CScriptID &scriptId) {
        CScript script;
        if (keystore.GetCScript(scriptId, script))
            Process(script);
    }
    void operator()(const CNoDestination &none) {}
};
void CWallet::GetKeyBirthTimes(std::map<CKeyID, int64_t> &mapKeyBirth) const {