Calling hideKeyguard more often, instead of caching it

Because we were caching the Keyguard state, we didn't call
hideKeyguard anymore when going to the shade locked and then
unlocking. As a consequence did we never update the public
mode and therefore remained in a wrong state.

Lot's of bad things could happen with it, for example did
inline reply not work anymore and the clear all button would
be hidden in certain cases. In general would the user not
be properly unlocked.

Test: manual, go to locked shade with redaction turned on, unlock via affordance, observe notifications are unlocked
Fixes: 62721741
Fixes: 62378400
Change-Id: Ibc757859ef26a1dba887e8986d6a2f8f2fe2efb4