Show/hide keyguard views whenever we tell WM lockscreen is visible.

This fixes issues with cancellation, where we were waiting
until the transition FINISHED to re-show keyguard views.
But hey, at least it was settling on the correct state
even prior to this fix!

Fixes: 300674764
Test: cancel GONE -> AOD transition inflight
Change-Id: I4b6c13c38002c6c0e2b8c221f6b4e4127bd67867