Merge changes from topic "camera" into p9.0

* changes:
  Fix crash if Exif-Tag buffer-length and component-count are both 0
  Camera2: Fix Undo button behaviour
  Camera2: Remove google help preference
  Camera2: Add option to set max screen brightness
  Camera: Powerkey shutter (2/2)
  Camera2: Request for ACCESS_FINE_LOCATION permission
  Camera2: Stop using GPS when going to background
  Camera2: Remove settings preferences only once
  Camera2: Only autofocus before a snap if we are actually in "auto" mode.
  Don't attempt to convert degree to orientation enum twice
  Camera2: Target API 27