In the log I see things like:

    2017-09-13 03:54:33 init message: Rescanning...
    2017-09-13 03:54:33 Rescanning last 68616 blocks (from block 416339)...
    2017-09-13 03:54:40 AddToWallet xxxxx  update
    2017-09-13 03:55:33 Still rescanning. At block 418849. Progress=0.549138

I would be interested to see the wallet file name on each of these log lines.

Would there be any interest in merging such a PR?
balances[addr] += n;
            }
        }
    }
    return balances;
}
std::set< std::set<CTxDestination> > CWallet::GetAddressGroupings()
{
    AssertLockHeld(cs_wallet); 
    std::set< std::set<CTxDestination> > groupings;
    std::set<CTxDestination> grouping;
    for (const auto& walletEntry : mapWallet)
    {
        const CWalletTx *pcoin = &walletEntry.second;
        if (pcoin->tx->vin.size() > 0)
        {
            bool any_mine = false;
            
            for (CTxIn txin : pcoin->tx->vin)
            {
                CTxDestination address;
                if(!IsMine(txin)) 
                    continue;
                if(!ExtractDestination(mapWallet.at(txin.prevout.hash).tx->vout[txin.prevout.n].scriptPubKey, address))
                    continue;
                grouping.insert(address);
                any_mine = true;
            }
            
            if (any_mine)