Handle confirm keys in Dreams.

This change adds handling confirm keys in Dreams to wake up and unlock
the device if the keyguard is insecure or bring up the bouncer prompt
on when the keyguard is secure. This change also removes logic to wakeup
from WindowManager when dismissing the keyguard while dreaming. This
logic is redundant as SystemUI already requests the device to wakeup
when unlocking while dreaming.

Fixes: 326975875
Flag: ACONFIG android.service.dreams.dream_handles_confirm_keys
Test: atest DreamServiceTest#testKeyHandling_InsecureKeyguardDismissesOnConfirmKey
Test: atest DreamServiceTest#testKeyHandling_SecureKeyguardConfirmKeyPromptsBouncer
Test: atest DreamServiceTest#testKeyHandling_InteractiveDreamConsumesConfirmNoWakeup
Test: atest DreamServiceTest#testKeyHandling_InteractiveDreamDoesNotConsumeConfirmPromptsBouncer
Change-Id: Ie080f694f87ae4bf26ebec09b333834da18e6d0c