Blender Git Loki

Fix T71868: Clay Strips brush collapsed geometry

We are now modifying the relation between pressure and radius using
custom functions to improve the brushes, but dyntopo was not prepared
for this. This fix sends the unmodified radius to dyntopo so it modifies
the geometry correctly.

Reviewed By: jbakker

Maniphest Tasks: T71868

Differential Revision: https://developer.blender.org/D6299