Allow handling power single press action when pressed during screen on.

1. Add a config config_supportShortPressPowerWhenScreenOn that can allow single-press power gesture triggered when screen is on and device is not interactive.
2. Store the default display state in SingleKeyGestureDetector.

This ensures that pressing power key during TTW optimization state can
open launcher.

Bug: 286592521
Test: adb shell am broadcast -a
  com.google.android.wearable.ambient.ACTION_FAKE_GAZE && adb shell input keyevent 26

Change-Id: Ia458d76c92289d2b6158efc909784bf85cb9d620