How to reproduce:
1. Create a new project in your Perforce Workspace folder
2. Open it and set it up to use Perforce
3. Change the asset database version
4. Save the project and reopen it
5. Observe the Perforce credential fields

Expected result: the fields are saved and are still filled out after the restart, perforce is connected automatically
Actual result: the fields are empty after the restart and perforce connection is broken

Reproduced in: 2019.3.0a9, 2019.3.0a1, 2019.2.0b9, 2019.2.0b4
Not reproducible in: 2019.2.0b3, 2019.2.0a6
Couldn't test with 2019.2.0a5, 2019.1.10f1, 2018.4.4f1, 2017.4.30f1 (no second asset pipeline version)

Note: reproduces both when switching from v1 to v2 and vice versa