Resetting Media DB re-selects internal storage as default storage

Description

If a user doesn't use the internal storage as a medialibrary root storage, when they delete their media database in the advanced settings, the app starts scanning the device using the internal storage as root.

This shouldn't be the case, and after deleting the media database, the app should reuse the previous roots

Steps to reproduce

1. Unselect internal storage in the Media library folders
2. Delete media database in the advanced settings
3. Try reopening the Media library folders, the app will show a snackbar saying that the medialibrary is indexing the device

Context

App version

3.6 Beta 6

App mode

Smartphone