How to reproduce:
1. Create a new HDRP project
2. Import the Hybrid Renderer package
3. Select Edit > Render Pipeline > Generate Shader Includes

Expected result: Shader Includes are generated
Actual result: InvalidCastException is thrown

Reproducible with: 2019.3.4f1, 2020.1.0b1, 2020.2.0a2
Could not test with: 2017.4.37f1(HDRP and Hybrid Renderer unavailable), 2018.4.18f1(regressed package version unavailable)

Reproducible with Hybrid Renderer package versions: preview.12 - 0.0.1, preview.15 - 0.3.5
Not reproducible with Hybrid Renderer package versions: preview.11 - 0.0.1

Notes:
Tested with HDRP 5.16.1 and 8.0.1
Issue stops reproducing when Hybrid Renderer is removed from the project