Revert "PasswordPolicy.getMinMetrics PIN"

This reverts commit 8dd50213.

Reason for revert: DroidMonitor: Potential culprit for Bug 185150796 - verifying through Forrest before revert submission. This is part of the standard investigation process, and does not mean your CL will be reverted.

Bug: 185150796
Change-Id: Ie6809d9e20b5c32c076e7a790095c65a2295781a