Fix the check for invalid characters in new passwords by switching from
PasswordMetrics#validatePassword() to
PasswordMetrics#validateCredential(). For more information, see
frameworks/base change I5c3c55367c3a294578cd0f97ac0e315a11ed517e.
Bug: 219511761
Bug: 232900169
Bug: 243881358
Test: Verified no regressions in 'atest ChooseLockPasswordTest'. Note,
this test is currently @Ignored and has 2 failures. I didn't
attempt to address that.
Test: Set a password containing non-ASCII characters on a device running
an older build. Upgraded and verified unlocking still works.
Tested that setting a new non-ASCII password is not allowed.
Change-Id: I5f1822a34688473cb103eb64dca56e4c19d4dd08
b547094366