https://travis-ci.org/github/bitcoin/bitcoin/jobs/679885530#L8791
{
        if (!old_tip.IsNull()) {
            LOCK(::cs_main);
            const CChain& active = Assert(m_node.chainman)->ActiveChain();
            if (old_tip == active.Tip()->GetBlockHash()) return;
        }
        SyncWithValidationInterfaceQueue();
    }
    std::unique_ptr<Handler> handleRpc(const CRPCCommand& command) override
    {
        return MakeUnique<RpcHandlerImpl>(command);
    }
    bool rpcEnableDeprecated(const std::string& method) override { return IsDeprecatedRPCEnabled(method); }
    void rpcRunLater(const std::string& name, std::function<void()> fn, int64_t seconds) override
    {
        RPCRunLater(name, std::move(fn), seconds);
    }
    int rpcSerializationFlags() override { return RPCSerializationFlags(); }
    util::SettingsValue getRwSetting(const std::string& name) override
    {
        util::SettingsValue result;
        gArgs.LockSettings([&](const util::Settings& settings) {
            if (const util::SettingsValue* value = util::FindKey(settings.rw_settings, name)) {
                result = *value;
            }
        });
        return result;
    }
    bool updateRwSetting(const std::string& name, const util::SettingsValue& value) override