Set project root path to the project layer immediately after loading the project so that project tree (expanded/collapsed) states can be restored.
Explicitly provide project root foler as layer ID so that new project-based keys can be created before recording view states in those keys.
Migrate project base url that I missed to convert since it is also one of the old preferences that uses the prefix with the project root path as keys.
Merge pull request #7004 from adobe/rlim/project-based-migration-issues

Fix three issues in project-based view states.