Show open padlock when keyguard is hidden

The device will be unlocked when the keyguard is not showing yet
because of a screen timeout or when the user disabled "power button
locks immediately." We need to present the correct state on AOD,
saying that the phone is unlocked.

Test: lock/unlock after screen off delay
Test: pulse after screen off delay (look at padlock)
Test: pulse after pressing power (look at padlock)
Test: lock/unlock after power button press
Fixes: 129316806
Change-Id: I2f0e401b61bb1df4a46ff2f9f78e27ea38f01fc0