Steps to repro:
1. Open the attached project and 'SampleScene' scene;
2. Let the scene's lighting auto-bake;
3. When the baking is completed, untoggle the Baked Global Illumination checkbox in the Lighting Settings;
4. When the baking is completed, enable the Baked Global Illumination checkbox in the Lighting Settings.

Expected result:
The light baking proceeds and finishes without errors or crashes.

Actual result:
Editor crashes with the empty stacktrace. See the attached video.
Regression introduced in Version 2019.3.0a1.

Notes:
- Reproducible in 2020.1.0a2, 2019.3.0b1, 2019.3.0a8, 2019.3.0a1;
- Not reproducible in 2019.2.4f1, 2019.1.14f1, 2018.4.8f1;
- Reproducible in Universal RP and HDRP; not reproducible in built-in pipeline;
- Reproducible on Windows and OSX;
- Reproducible only when baking with CPU Lightmapper, not reproducible with GPU Lightmapper or Enlighten;
- In some cases right before the crash OpenRL errors code 501 and 502 are shown in the Console;
- In 2019.3.0a1 the crash is repoducible after initiallly opening the scene with auto-bake, this seems fixed in the later 2019.3 versions.