Caused by a67b5f6f63
Since we dont necessarily act with `MeshExtractType::BMesh` (can be
`MeshExtractType::Mesh` as well -- and seems the specific mesh analysis
`statvis_calc` functions are well prepared for this), move access to
`BMesh` to the codepaths specific to `MeshExtractType::BMesh`.
Also remove (non-appropriate) assert in `extract_mesh_analysis`.
Pull Request: https://projects.blender.org/blender/blender/pulls/139717