QTextEdit crashes application when pasting with empty clipboard

What happens

When you have an empty clipboard (e.g. after booting the computer) and call the paste command inside a QTextEdit, the process will crash.

What should happen

The paste should have no effect in the QTextEdit.

How to reproduce

• Reboot the computer (to clear the clipboard). Make sure you copy nothing to the clipboard.
• Start the Text Edit sample application.
• Click on the first block of the QTextEdit.
• Hit CTRL + V on the keyboard.

Note that the application will crash.