policy: respect FLAG_TURN_SCREEN_ON flag with device flip covers

If an application uses WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
and the device supports covers and the cover is closed, then after the
screen would turn on due to this flag, it would immediately be turned off
because PhoneWindowManager thinks the cover is closed, so it puts the device to
sleep.

Respect this flag and do nothing if it is detected.

Change-Id: I7eb36ce676730e47c551518e214b08561c401ea5
Signed-off-by: Roman Birg <roman@cyngn.com>
frameworks: allow last app action to be assigned to hardware keys

Also fix multi-user handling for 'switch to last app' and 'kill
foreground app' actions.

Change-Id: I1fb586d19b1198e6888b0f11e0a2813acf0bcd5b
Signed-off-by: Roman Birg <roman@cyngn.com>
Signed-off-by: Danny Baumann <dannybaumann@web.de>