Compile master, and run with `src/qt/bitcoin-qt -regtest -nowallet`. As expected, no icon is displayed. Load and unload a wallet. The `HD` icon remains.

On startup:
![on_startup](https://user-images.githubusercontent.com/863730/72410834-711b4c00-37a4-11ea-9a10-bfcf3db7ce68.png)

After a wallet load and unload:
![after_load_unload](https://user-images.githubusercontent.com/863730/72410838-737da600-37a4-11ea-8854-dd13301c0135.png)

connect(toggleHideAction, &QAction::triggered, this, &BitcoinGUI::toggleHidden);
    connect(showHelpMessageAction, &QAction::triggered, this, &BitcoinGUI::showHelpMessageClicked);
    connect(openRPCConsoleAction, &QAction::triggered, this, &BitcoinGUI::showDebugWindow);
    
    connect(quitAction, &QAction::triggered, rpcConsole, &QWidget::hide);
#ifdef ENABLE_WALLET
    if(walletFrame)
    {
        connect(encryptWalletAction, &QAction::triggered, walletFrame, &WalletFrame::encryptWallet);
        connect(backupWalletAction, &QAction::triggered, walletFrame, &WalletFrame::backupWallet);
        connect(changePassphraseAction, &QAction::triggered, walletFrame, &WalletFrame::changePassphrase);
        connect(signMessageAction, &QAction::triggered, [this]{ showNormalIfMinimized(); });
        connect(signMessageAction, &QAction::triggered, [this]{ gotoSignMessageTab(); });
        connect(verifyMessageAction, &QAction::triggered, [this]{ showNormalIfMinimized(); });
        connect(verifyMessageAction, &QAction::triggered, [this]{ gotoVerifyMessageTab(); });
        connect(usedSendingAddressesAction, &QAction::triggered, walletFrame, &WalletFrame::usedSendingAddresses);
        connect(usedReceivingAddressesAction, &QAction::triggered, walletFrame, &WalletFrame::usedReceivingAddresses);
        connect(openAction, &QAction::triggered, this, &BitcoinGUI::openClicked);
        connect(m_open_wallet_menu, &QMenu::aboutToShow, [this] {
            m_open_wallet_menu->clear();
            for (const std::pair<const std::string, bool>& i : m_wallet_controller->listWalletDir()) {
                const std::string& path = i.first;
                QString name = path.empty() ? QString("["+tr("default wallet")+"]") : QString::fromStdString(path);
                
                
                
                name.replace(name.indexOf(QChar('&')), 1, QString("&&"));
                QAction* action = m_open_wallet_menu->addAction(name);
                if (i.second) {