A call to `removeprunedfunds` does not update the transaction list in the GUI, and trying to access the info of a deleted transaction will result in a segfault.

```bash
(lldb) run
Process 4859 launched: '/Users/michael/github/bitcoin/src/qt/bitcoin-qt' (x86_64)
2019-09-24 15:41:53.763094+0800 bitcoin-qt[4859:390268] MessageTracer: Falling back to default whitelist
Process 4859 stopped
* thread #1, name = 'bitcoin-main', queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x34)
    frame #0: 0x00000001001c9bf6 bitcoin-qt`TransactionDesc::FormatTxStatus(wtx=0x00007ffeefbfc0e0, status=0x00007ffeefbfc0c0, inMempool=false, numBlocks=1) at transactiondesc.cpp:33:31
   30  	{
   31  	    if (!status.is_final)
   32  	    {
-> 33  	        if (wtx.tx->nLockTime < LOCKTIME_THRESHOLD)
   34  	            return tr("Open for %n more block(s)", "", wtx.tx->nLockTime - numBlocks);
   35  	        else
   36  	            return tr("Open until %1").arg(GUIUtil::dateTimeStr(wtx.tx->nLockTime));
Target 0: (bitcoin-qt) stopped.
```
walletInstance->m_min_fee = CFeeRate(n);
    }
    walletInstance->m_allow_fallback_fee = Params().IsTestChain();
    if (gArgs.IsArgSet("-fallbackfee")) {
        CAmount nFeePerK = 0;
        if (!ParseMoney(gArgs.GetArg("-fallbackfee", ""), nFeePerK)) {
            chain.initError(strprintf(_("Invalid amount for -fallbackfee=<amount>: '%s'").translated, gArgs.GetArg("-fallbackfee", "")));
            return nullptr;
        }
        if (nFeePerK > HIGH_TX_FEE_PER_KB) {
            chain.initWarning(AmountHighWarn("-fallbackfee").translated + " " +
                              _("This is the transaction fee you may pay when fee estimates are not available.").translated);
        }
        walletInstance->m_fallback_fee = CFeeRate(nFeePerK);
        walletInstance->m_allow_fallback_fee = nFeePerK != 0; 
    }
    if (gArgs.IsArgSet("-discardfee")) {
        CAmount nFeePerK = 0;
        if (!ParseMoney(gArgs.GetArg("-discardfee", ""), nFeePerK)) {
            chain.initError(strprintf(_("Invalid amount for -discardfee=<amount>: '%s'").translated, gArgs.GetArg("-discardfee", "")));
            return nullptr;
        }
        if (nFeePerK > HIGH_TX_FEE_PER_KB) {
            chain.initWarning(AmountHighWarn("-discardfee").translated + " " +
                              _("This is the transaction fee you may discard if change is smaller than dust at this level").translated);
        }
        walletInstance->m_discard_rate = CFeeRate(nFeePerK);
    }
    if (gArgs.IsArgSet("-paytxfee")) {
        CAmount nFeePerK = 0;