KeyguardStateMonitor looses connection with keystore if keystore dies

KeyguardStateMonitor looses connection with keystore if keystore dies

When keystore dies it no longer gets information about the lock screen
visibility state. This state is vital to enforcing the "unlocked
device required" authorization of keymaster keys.

With this patch KeyguardStateMonitor tries to reestablish the connection
to keystore if communication fails.

Test: run atest android.keystore.cts.CipherTest#testKeyguardLockAndUnlock
      after killing keystore
Bug: 117552147

Change-Id: I8346e53c342bdba0f5960b1feba7c26db5cef33e