When there is no color layer available,
BKE_sculpt_update_object_for_edit creates a new one and tags the mesh
with ID_RECLAC_GEOMETRY, so this layer is inmediatly available when the
tool starts. This also deletes the PBVH and when it is created again in
BKE_sculpt_update_object_after_eval, the pmap is not initialized, making
the tool crash.
This moves the color layer creation to a separate function outside
BKE_sculpt_update_object_for_edit, which now runs after the color
layer is available, so it won't need to update again and the pmap will
still be available when the tool is used.
Reviewed By: sergey
Maniphest Tasks: T78242
Differential Revision: https://developer.blender.org/D8135
4f3233dd53