Fix the physics related crashing

[hhyyrylainen]

Quite a few reports have come in about the game locking up and spamming this message:

**ERROR**: Condition "p_node == _data._nil && p_color == RED" is true.
   At: ./core/map.h:154:_set_color() - Condition "p_node == _data._nil && p_color == RED" is true.

repeating infinitely.
One full log file: https://pastebin.com/VPPxKBuQ
It seems to happen on physics contact (attacking with the pilus, respawning).
Might be related to: #1126

[hhyyrylainen]

One more log: https://pastebin.com/0ePs5YFm
This seems to happen on return from editor. So I'm going to say that physics things touching (with certain random stuff having happened before) is what triggers the problem.

[hhyyrylainen]

Possibly related report on the forums: https://community.revolutionarygamesstudio.com/t/crash-while-playing/2647?u=hhyyrylainen

[hhyyrylainen]

Possibly relevant godot bug: godotengine/godot#37652

[hhyyrylainen]

This might be the reason also for random crashing of the game, though that's way less confirmed.

[hhyyrylainen]

Probably one more instance of this bug being reported: https://community.revolutionarygamesstudio.com/t/fatal-crash-pushing-iron-chunk-with-big-cell/3211?u=hhyyrylainen

[hhyyrylainen]

This might be more likely to be caused when making your cell a stick. At least this youtuber experiences this often: https://youtu.be/GQO-TGaji-Y
Doesn't seem to be a difference between horizontal and vertical stick cells.

[hhyyrylainen]

This might be fixed with Godot 3.3, so after the next release we'll need to check if this still happens or not.

[hhyyrylainen]

I renamed this issue to be more accurate. Recently with out crash reporting system back, I think almost 100% of crashes on Windows are either some weird memory corruption somewhere or crashing in the physics system, I suspect both are actually the same problem. Surprisingly it seems like no Linux reports have come in with a crash like this so this might be a Windows only problem.

[hhyyrylainen]

Related physics problem: #2339