[Linux][IMGUI] Sprite Icons are not visible in Asset Selector Window

Sprite Icons are not visible in Asset Selector Window

Steps to reproduce:

1. Create a new Project
2. Hierarchy > right-click > 2D > Sprite
3. Select New Sprite > Inspector > Sprite Renderer > Sprite > Asset Selector icon

Expected Result: Asset Selector Window should be opened with icons

Actual Result: Asset Selector Window should be opened without icons

Reproducible on: 2020.1.0a5, 2019.3.0b4, 2019.2.0a1

Working Fine on: 2019.1.10f1, 2018.3.1f1

Environment: Linux (ubuntu 16.04 LTS)