1. Decrease transient navigation confirmation annoyance.
- Only use the power-key as a signal if we detect a screen-off
screen-on within a short threshold value.
- Auto-confirm if user performs the indicated gesture.
- Remember confirmation across reboots.
2. Update wording to new final wording. Remove now obsolete
short + long versions. Decrease message font temporarily
until the new platform toast redesign is finalized.
3. Remove pre-ship ImmersiveModeTesting debug helper.
Bug:10602929
Change-Id: I0bff826391058c7b282eeb61817b93b79de84893
d67ec25a9c