### Describe the issue

Testing in bitcoin 0.13.0, calling `bitcoin-cli listsinceblock x` is outputting all double-spent transactions that are in the wallet, even those that were double-spent well and truly before x.
### Is the issue reproducible?

Yes
#### List steps to reproduce below:
1.   Create a double-spend send to your wallet (easiest using bip125)
2.   Wait until one confirms, and then wait a few more blocks
3.   Run `bitcoin-cli listsinceblock $(bitcoin-cli getbestblockhash)` and it will output the double spent transaction
### Expected behavior

The double-spent transaction that was conflicted before the block hash should be filtered

"This is for use with raw transactions, NOT normal use.\n",
                {
                    {"address_type", RPCArg::Type::STR,  "set by -changetype", "The address type to use. Options are \"legacy\", \"p2sh-segwit\", and \"bech32\"."},
                },
                RPCResult{
            "\"address\"    (string) The address\n"
                },
                RPCExamples{
                    HelpExampleCli("getrawchangeaddress", "")
            + HelpExampleRpc("getrawchangeaddress", "")
                },
            }.Check(request);
    LOCK(pwallet->cs_wallet);
    if (!pwallet->CanGetAddresses(true)) {
        throw JSONRPCError(RPC_WALLET_ERROR, "Error: This wallet has no available keys");
    }
    OutputType output_type = pwallet->m_default_change_type != OutputType::CHANGE_AUTO ? pwallet->m_default_change_type : pwallet->m_default_address_type;
    if (!request.params[0].isNull()) {
        if (!ParseOutputType(request.params[0].get_str(), output_type)) {
            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, strprintf("Unknown address type '%s'", request.params[0].get_str()));
        }
    }
    CTxDestination dest;
    std::string error;
    if (!pwallet->GetNewChangeDestination(output_type, dest, error)) {
        throw JSONRPCError(RPC_WALLET_KEYPOOL_RAN_OUT, error);
    }
    return EncodeDestination(dest);
}
static UniValue setlabel(const JSONRPCRequest& request)