Create a wallet as follows:

```sh
$ bitcoin-cli createwallet "watchonly" true
$ bitcoin-cli -rpcwallet=watchonly getwalletinfo
{
   ...
   "private_keys_enabled": false
}
```

The following should fail, but doesn't:

```sh
$ bitcoin-cli -rpcwallet=watchonly encryptwallet 1234
wallet encrypted; The keypool has been flushed and a new HD seed was generated (if you are using HD). You need to make a new backup.
```

It partially fails silently, because it doesn't actually add a seed. But it does ask for a password when calling `dumpwallet`, which doesn't make sense because we currently don't encrypt anything other than private keys.  
CAmount nAmount = AmountFromValue(request.params[1]);
    if (nAmount <= 0)
        throw JSONRPCError(RPC_TYPE_ERROR, "Invalid amount for send");
    
    mapValue_t mapValue;
    if (!request.params[2].isNull() && !request.params[2].get_str().empty())
        mapValue["comment"] = request.params[2].get_str();
    if (!request.params[3].isNull() && !request.params[3].get_str().empty())
        mapValue["to"] = request.params[3].get_str();
    bool fSubtractFeeFromAmount = false;
    if (!request.params[4].isNull()) {
        fSubtractFeeFromAmount = request.params[4].get_bool();
    }
    CCoinControl coin_control;
    if (!request.params[5].isNull()) {
        coin_control.m_signal_bip125_rbf = request.params[5].get_bool();
    }
    if (!request.params[6].isNull()) {
        coin_control.m_confirm_target = ParseConfirmTarget(request.params[6], pwallet->chain().estimateMaxBlocks());
    }
    if (!request.params[7].isNull()) {
        if (!FeeModeFromString(request.params[7].get_str(), coin_control.m_fee_mode)) {
            throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid estimate_mode parameter");
        }
    }
    EnsureWalletIsUnlocked(pwallet);
    CTransactionRef tx = SendMoney(*locked_chain, pwallet, dest, nAmount, fSubtractFeeFromAmount, coin_control, std::move(mapValue));
    return tx->GetHash().GetHex();
}
static UniValue listaddressgroupings(const JSONRPCRequest& request)