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?
{
    LOCK(cs_wallet);
    std::set<CTxDestination> result;
    for (const std::pair<const CTxDestination, CAddressBookData>& item : mapAddressBook)
    {
        const CTxDestination& address = item.first;
        const std::string& strName = item.second.name;
        if (strName == label)
            result.insert(address);
    }
    return result;
}
void CWallet::DeleteLabel(const std::string& label)