Apps stops suddenly if Particle System

[Jaysmito Mukherjee]

Description
Sometimes while using the particle system(not in any other case) the window stops working if it is resized or if the frame delay is changed.

To Reproduce
Steps to reproduce the behavior:

1. Go to example-apps/fireworks
2. Start up run.bat
3. Try randomly resizing the window
4. OR
5. Try changing the frame delay from Control Panel

Expected behavior
Expected behavior is that it will just not crash.

Screenshots

[Jaysmito Mukherjee]

This has been fixed in 88c659e