There is an assert in `CWalletTx::RelayWalletTransaction` that gets hit.  All other code paths check `fBroadcastTransactions` before getting to `CWallet::ResendWalletTransactionsBefore` except the rpc call `resendwalletransactions`.

It's an easy fix, but we just need to decide whether to throw an error or return an empty array of rebroadcasted transaction ids.

Should be fixed for 0.15.
{
    CWallet * const pwallet = GetWalletForJSONRPCRequest(request);
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp))
        return NullUniValue;
    if (request.fHelp || request.params.size() < 1 || request.params.size() > 2) {
        throw std::runtime_error(
            "bumpfee \"txid\" ( options ) \n"
            "\nBumps the fee of an opt-in-RBF transaction T, replacing it with a new transaction B.\n"
            "An opt-in RBF transaction with the given txid must be in the wallet.\n"
            "The command will pay the additional fee by decreasing (or perhaps removing) its change output.\n"
            "If the change output is not big enough to cover the increased fee, the command will currently fail\n"
            "instead of adding new inputs to compensate. (A future implementation could improve this.)\n"
            "The command will fail if the wallet or mempool contains a transaction that spends one of T's outputs.\n"
            "By default, the new fee will be calculated automatically using estimatefee.\n"
            "The user can specify a confirmation target for estimatefee.\n"
            "Alternatively, the user can specify totalFee, or use RPC settxfee to set a higher fee rate.\n"
            "At a minimum, the new fee rate must be high enough to pay an additional new relay fee (incrementalfee\n"
            "returned by getnetworkinfo) to enter the node's mempool.\n"
            "\nArguments:\n"
            "1. txid                  (string, required) The txid to be bumped\n"
            "2. options               (object, optional)\n"
            "   {\n"
            "     \"confTarget\"        (numeric, optional) Confirmation target (in blocks)\n"
            "     \"totalFee\"          (numeric, optional) Total fee (NOT feerate) to pay, in satoshis.\n"
            "                         In rare cases, the actual fee paid might be slightly higher than the specified\n"
            "                         totalFee if the tx change output has to be removed because it is too close to\n"
            "                         the dust threshold.\n"
            "     \"replaceable\"       (boolean, optional, default true) Whether the new transaction should still be\n"