Fix DomainVerificationService deadlock

Enforces the PackageManagerService lock to be taken before the DVS lock,
when neccessary, so that the locking is always one-way and cannot
deadlock when Settings attempts to serialize state.

Bug: 183643808

Test: manual run CTS which previously reproduced this issue

Change-Id: Ibccde458df16238755f3a67080321cb3ebdf7233