StackOverflowException when painting on any non-Unity object using WorldPoint or Nearest Surface Point on MousePainter

[mrcoolisimo]

This seems to be because WorldPoint defaults to PaintNearestTriangleSurface() which then triggers an endless loop. To reproduce this, go to blender, use any basic object such as a sphere, and attempt to paint it. About halfway down the sphere, Unity will freeze for about a minute, multiple "Could not get point on surface" messages will appear, and then finally a StackOverflowException. I've also tested this on imported models on the asset store with similar results.