Refreshing Android device list hides actual devices

Steps to reproduce:

1. Select Android 5.15.6 as target kit.
2. Click the "Run" button. A device selection dialog is shown with the Android simulators and connected real devices.
3. Press the "Refresh" button. The real devices disappear if pressing the button multiple times.
4. Close the device selection dialog.
5. Press the "Run" button again. Now the real devices are shown again.