How to reproduce:
1. Open user-submitted project (Unity_Testing-master)
2. Open the SampleScene
3. Select and focus on the 'Door_ProbuilderizeThis' GameObject
4. Open Tools > Probuilder > Probuilder Window
5. Select 'Probuilderize'

Expected result: the door looks the same as before Probuilderizing
Actual result: the door's faces have the wrong material applied after Probuilderizing

Reproducible with Unity versions: 2019.1.0a10, 2019.1.6f1, 2019.2.0b5, 2019.3.0a5
Not reproducible with Unity versions: 2018.4.2f1, 2019.1.0a9
Could not test with Unity versions: 2017.4.28f1(ProBuilder package not available)

Reproducible with package versions: 4.0.2, 4.0.5
Not reproducible with package versions: 3.0.9

Notes:
"Not reproducible" Unity versions were only tested with the non-regressed package version, since the regressed versions were incompatible