LockscreenPattern : Toggle dots/error pattern visibility (2/2)

Give user ability to hide error pattern / dots.

Patchset 2 : Cleanup commit msg

Change-Id: Ifdd4615c7116f974a0a67079d58a521e84d76367
LockscreenPattern: Fix toggle dots/error pattern visibility

This fix the issues dot/error pattern state doesn't save.
also cleanup redundant code.

Change-Id: Iebaac9679ad9c621d62effd700689485db7c252a