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.
```
{
    AssertLockHeld(cs_wallet);
    if (keypool.m_pre_split) {
        set_pre_split_keypool.insert(nIndex);
    } else if (keypool.fInternal) {
        setInternalKeyPool.insert(nIndex);
    } else {
        setExternalKeyPool.insert(nIndex);
    }
    m_max_keypool_index = std::max(m_max_keypool_index, nIndex);
    m_pool_key_to_index[keypool.vchPubKey.GetID()] = nIndex;
    
    
    
    CKeyID keyid = keypool.vchPubKey.GetID();
    if (mapKeyMetadata.count(keyid) == 0)
        mapKeyMetadata[keyid] = CKeyMetadata(keypool.nTime);
}
bool CWallet::TopUpKeyPool(unsigned int kpSize)
{
    if (!CanGenerateKeys()) {
        return false;
    }
    {
        LOCK(cs_wallet);
        if (IsLocked()) return false;
        
        unsigned int nTargetSize;
        if (kpSize > 0)