Widget component does not update when setting widget class back to "None"

Widget component does not update when setting widget class back to "None". When the widget class is returned to "None" the user can still see the previous widget in the viewport. The blueprint must be closed and then reopened before the ghost of the last widget is removed.

1. Open the editor
2. Create a new widget blueprint
3. Add an image to the top left of the designer tab
4. Compile and save
5. Create a new actor blueprint
6. Add a widget component
7. Set the widget component's widget class to the newly created widget blueprint
8. Set the "Draw desired Size" to true
9. Compile and save
10. Set the Widget component's Widget class to "None"
11. Compile
12. Notice that the widget class does not visually return to "None" but stays as the widget class that was previously assigned

Expected: The widget class would return to none visually back to "None" when changing the widget class for the widget component
Result: When the widget class is returned to "None" the user can still see the previous widget in the viewport