The baking get stuck when the static object starts to bake with Progressive GPU light mapper the second time.
[PathTracer] Failed to add geometry for mesh 'Cube'; mesh is missing required attribute(s) error is thrown in the console.

Prerequisites: you'll need to have the machine with GPU having <4GB of VRAM

Steps to repro:
1. Create a new Project.
2. Create a static Cube game object.
3. Windows > Rendering > Light Settings.
4. Lightmapping Settings > Lightmapper.
5. Select Progressive GPU(Preview).
6. Bake
7. Lightmapper falls back to CPU.
8. Select Progressive GPU(Preview).
9. Bake

Actual Result:
-Baking stalls when the static object starts to bake.
-[PathTracer] Failed to add geometry for mesh 'Cube'; mesh is missing in the console.

Expected Result:
-Baking should not be stuck.
-No Errors in the console.

Reproducible in:
2020.1.0a18, 2020.1.0a17.

Working Fine in:
2020.1.0a16, 2019.3.0f5(4b9e60e5c3e9).

Environment:
Occurs only on Windows.

Stack trace:
[PathTracer] Failed to add geometry for mesh 'Cube'; mesh is missing required attribute(s). Please make sure the mesh contains at least positions, normals and texcoord0.