Reset functionality is not working for Occulusion Portal

Steps to Reproduce:

1. Create a new project
2. Hierarchy > right-click > Gameobject
3. GameObject > Inspector > Add Component > Rendering > Occulusion Portal
4. GameObject > Inspector > Occulusion Portal
5. Change values of Open, Center and Size
6. Cogwheel > reset

Actual Result: Default value is not set

Expected Result: Default values should be set

Reproducible on:
2019.3.0a5, 2019.2.0b5, 2019.1.0f2, 2018.3.0f2

Environment: Mac 10.14 and Windows 10