Demote SecurityException in DPMS.reportPasswordChanged

reportPasswordChanged is called on a handler thread so it might
be invoked much later than a password change, in which case the
original assumption about the device state might not be satisfied
any more. Demote a precondition check to a mere warning in case
reportPasswordChanged is called on an unexpected user.

Bug: 394991242
Test: ManagedProfilePasswordTest
Flag: EXEMPT bugfix
Change-Id: I29a1df3b12512f76225a602cf990b2ec76486af8