I was messing around with min relay policies and found that under certain circumstances the mempool will accept things, then not relay to any peers.

Example made using wallet:
Transaction of size 6195, fee of 619 satoshis, minrelay of 100 satoshis per kvB. Mempool logic allows it:

```
        // No transactions are allowed below minRelayTxFee except from disconnected blocks
        if (!bypass_limits && nModifiedFees < ::minRelayTxFee.GetFee(nSize)) {
            return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "min relay fee not met", false, strprintf("%d < %d", nModifiedFees, ::minRelayTxFee.GetFee(nSize)));
        }
```
and lets it into mempool

but in net_processing.cpp:

```
                    if (filterrate && txinfo.feeRate.GetFeePerK() < filterrate) {
                        continue;
                    }
```
this gets hit because the computed feerate is insufficient(printing I added):
```
0.00000099 BTC/kB
```

I'm not super at arithmetic so I'm opening this up in case someone has an easy fix. 

let me also get a reproducible test failure with this...
{
    LOCK(cs);
    mapDeltas.erase(hash);
}
const CTransaction* CTxMemPool::GetConflictTx(const COutPoint& prevout) const
{
    const auto it = mapNextTx.find(prevout);
    return it == mapNextTx.end() ? nullptr : it->second;
}
boost::optional<CTxMemPool::txiter> CTxMemPool::GetIter(const uint256& txid) const
{
    auto it = mapTx.find(txid);
    if (it != mapTx.end()) return it;
    return boost::optional<txiter>{};
}
CTxMemPool::setEntries CTxMemPool::GetIterSet(const std::set<uint256>& hashes) const
{
    CTxMemPool::setEntries ret;
    for (const auto& h : hashes) {
        const auto mi = GetIter(h);
        if (mi) ret.insert(*mi);
    }
    return ret;
}
bool CTxMemPool::HasNoInputsOf(const CTransaction &tx) const