How to reproduce it:
1. Open user's attached project
2. Load 'TreeBoundsTest' scene from 'Assets' folder
3. Clear Console view
4. In the Hierarchy window click on the 'Terrain' GameObject
5. In the Inspector view find a 'Terrain' component and disable it
6. Enable 'Terrain' component
7. Notice that in the Console view warnings occur

Expected result: There are no warnings in the Console view
Actual result: Warnings occur with the message: "The bounds contain one of the following values: NaN, float.PositiveInfinity, float.NegativeInfinity. All values in bounds are reset to zero."

Reproducible with: 2020.2.0a8, 2020.2.0b4
Not reproducible with: 2020.1.0a19, 2020.1.6f1, 2020.2.0a7
Could not test with: 2019.4.11f1, 2020.1.0a18 (due to errors)

Note: If in the Inspector view 'tree_Birch_LOD0' and 'tree_Birch_LOD1' will be removed from the 'Tree Birch' prefab, and then 4 - 7 steps will be repeated, the Console view will not show any warnings