Blender Git Loki

"Fix" for #17636 Crashing bug - won't open a file
- The cause was indeed corrupted particle settings which should have caused a deletion of the whole particle system. However the particle modifier was still left and that led to the crash.
- A "fix" because there's really no way of knowing what caused the corruption of the particle settings. If anyone else gets this and can recreate I'd love to get a .blend. Now that there shouldn't be a crash anymore the symptom will be a missing particle system after file load in an object that had a particle system before.