Refactored KeyguardIndicationController and LockIcon.

Notes:
- KeyguardIndicationController can now be provided via the SystemUIFactory.
- Created a BaseKeyguardCallback to allow extention of KIC callback implementation.
- LockIcon can now be extended through the KIC to support an avatar icon for entering trust.

Test: runtest systemui
Bug: 34589272
Change-Id: I3a8745dc5054841155a6db41c7e5e8ae5ae1f30d