Revert "Revert "Add support for enabling backup in work profile in""

This reverts commit 0bfafb7f411a57fd576afa9d30b66885ab7831ab.

Reason for revert: Removing enforceUnlocked() should fix the bug and Backup now supports it.

Change-Id: Id06f63c62b0f43cd70da77df48674146d4cc0412
2 files changed