Print String stop printing to screen after simulating in viewport

REGRESSION: Yes
WORKING: 3031272
BROKEN: 3031715

Print String will no longer print on the screen once the user simulates in viewport. Play in viewport will work, but once simulate in viewport happens, it won't work in either.

It still prints in the Output Log.

1. Open QAGame in editor.
2. Create a new actor blueprint and open it.
3. Drag off the Event Tick node and add a Print String node.
4. Compile it.
5. Add it do the level.
6. Play in viewport. Notice that the string prints on the screen.
7. Exit PIE, then simulate in viewport. Notice it doesn't print.
8. Exit Simulation, and the play in viewport again. It no longer prints on screen.