Transparency for Widget components is not working on iOS devices

If the user has a widget with an opacity less than 1 it will be rendered as though the opacity was set to 1 on iOS devices

Note: Possible regression

1. Open the Editor
2. Create A new widget blueprint
3. Add an image to the designer tab
4. Set it's size to 500 by 500 (so that it's easier to see)
5. Set the opacity for the image to .5
6. Save and compile
7. Create a new actor blueprint
8. Add a widget component
9. Set the class for the widget component to the widget blueprint that was just created
10. Add the actor to the scene
11. Launch the project to an iOS device
12. Notice that the 3d Widget is not translucent

Expected: The 3D widget would be partially transparent
Result: The 3D widget is not transparent at all