1. What happened
[2D][Sprite Renderer] Sprite in Sprite Renderer goes missing when upgrading project from 2018.3 to 2019.1 or 2019.2

2. How we can reproduce it using the example you attached

Repro steps:

Create a fresh new project with 2018.3.4f1 onwards:
1. Create a sprite from multiple mode using a single texture in 2018.3
2. Put Sprite in scene with a sprite renderer
3. Upgrade project to 2019.1 or 2019.2
4. Note that Sprite in Sprite Renderer goes missing when upgrading project

Additional Note:
Reopening the project in 2018.3 causes the sprite to reappear back in sprite renderer