Noticed this while reviewing #13529, but it's also in master @ 5ba77df15. On macOS 10.13.6:

```
bitcoin-qt -disablewallet
```

<img width="1354" alt="schermafbeelding 2018-08-01 om 16 03 41" src="https://user-images.githubusercontent.com/10217/43526506-b23264d8-95a4-11e8-81a0-5debcad838ae.png">

The usual progress modal doesn't appear when QT starts, and clicking on the progress bar has no effect. It works fine when there's a wallet present.
#include <qt/bitcoingui.h>
#include <qt/bitcoinunits.h>
#include <qt/clientmodel.h>
#include <qt/guiconstants.h>
#include <qt/guiutil.h>
#include <qt/modaloverlay.h>
#include <qt/networkstyle.h>
#include <qt/notificator.h>
#include <qt/openuridialog.h>
#include <qt/optionsdialog.h>
#include <qt/optionsmodel.h>
#include <qt/platformstyle.h>
#include <qt/rpcconsole.h>
#include <qt/utilitydialog.h>
#ifdef ENABLE_WALLET
#include <qt/walletframe.h>
#include <qt/walletmodel.h>
#include <qt/walletview.h>
#endif 
#ifdef Q_OS_MAC
#include <qt/macdockiconhandler.h>
#endif
#include <chainparams.h>
#include <interfaces/handler.h>
#include <interfaces/node.h>
#include <ui_interface.h>
#include <util/system.h>
#include <iostream>
#include <QAction>