When a widget is Anchored for full screen but is outside of the canvas panel this can cause a memory leak

If the user places a text widget out side of the canvas panel and then sets it's anchor point to full screen, this can cause a memory leak (100kb-800kb).

1. Open the editor
2. Create a New widget blueprint
3. Open the level blueprint
4. Add the widget to the screen
5. Save
6. Play in editor
7. Open the task manager and notice that the memory usage of the editor is not constantly climbing
8. Stop PIE
9. Open the widget blueprint
10. Place a text in the designer tab
11. Move the text outside of the canvas panel
12. Set the anchor for the text to fullscreen
13. PIE
14. Open the task manager and notice that the memory usage of the editor is constantly climbing

Expected: The Memory usage would stabilize
Result: The memory usage keeps climbing