addmultisigaddress creates an address respecting the setting, being unable to generate a specific type of address without also adding it to the wallet seems wrong.

I suppose in the future `addresstype` may be refactored to be wallet-specific, which would leave this non-wallet rpc call without an argument. Perhaps there should just be an optional parameter to set it.
{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
    if (request.fHelp || request.params.size() < 1 || request.params.size() > 3)
        throw std::runtime_error(
            "signrawtransactionwithwallet \"hexstring\" ( [{\"txid\":\"id\",\"vout\":n,\"scriptPubKey\":\"hex\",\"redeemScript\":\"hex\"},...] sighashtype )\n"
            "\nSign inputs for raw transaction (serialized, hex-encoded).\n"
            "The second optional argument (may be null) is an array of previous transaction outputs that\n"
            "this transaction depends on but may not yet be in the block chain.\n"
            + HelpRequiringPassphrase(pwallet) + "\n"
            "\nArguments:\n"
            "1. \"hexstring\"                      (string, required) The transaction hex string\n"
            "2. \"prevtxs\"                        (string, optional) An json array of previous dependent transaction outputs\n"
            "     [                              (json array of json objects, or 'null' if none provided)\n"
            "       {\n"
            "         \"txid\":\"id\",               (string, required) The transaction id\n"