Value in luminance validation dropdown doesn't change in PBR Validation Settings on switching the draw mode from shaded to validate albedo.

Steps to repro:
1. Create a new project.
2. Scene View > Change the draw mode from Shaded to Validate Albedo under material validation.
3. Change the value in luminance validation dropdown.

Actual Result:
Luminance validation value in dropdown does not change to the selected one.

Expected Result:
Luminance validation value in dropdown changes to the selected one.

Occurring on:
2020.2.0a11,2020.1.0b9,2020.1.0a26

Working fine in:
2020.1.0a25, 2019.3.14f1.

Occuring On:
Only on macOS 10.14