Added changes for storing PIN length in PasswordData

This CL aims at adding changes for storing PIN length in PasswordData
class. This would make it more secure and also help us fix any race
conditions.

Bug: b/267222046
Test: Tested by building and flashing on local
Change-Id: I54023c36ab671baeb6c6e6020c78d1f86a00e75e
6 files changed