Angular damp inside Area is far too strong

[Garmelon]

Godot version:
3.2.1-stable (b0eca58, self-compiled)
Also happens in the latest version on the 3.2.2 branch (757d8b5)

OS/device including version:
Arch linux

Issue description:

Expected behaviour:
A RigidBody inside an Area with default settings and spatial override set to Replace behaves the same as a RigidBody outside of the Area, if the project physics settings have not been changed.

Actual behaviour:
The Area seems to apply very high actual angular damp even though it is set to the same value as the project physics settings (0.1).

Steps to reproduce:

1. Create a new project with a 3D scene
2. Add a floor StaticBody, a camera and maybe some lights
3. Add an Area and give it a collision shape. Set its spatial override to Replace
4. Add RigidBodys about to tip over inside and outside of the Area
5. Run the scene

Minimal reproduction project:
bug_area_angular_damp.zip

Demo gif:

[madmiraal]

Only happens with Bullet physics. Godot physics is fine.

[AndreaCatania]

This is already fixed in 4.0 by this PR: #37314
Can we back port that change?

[akien-mga]

It requires updating bullet to a non-stable version, I'm not sure it would be a good idea for 3.2.x.
Might be better to document the bug then.

[madmiraal]

I've created a 3.2 backport of #37314: #39084. However, this issue still remains.

[Garmelon]

Well, that was quick. Thanks for the fix