Move VR preference for portrait orientation.

This code as written had two problems:
1) It assumed ROTATE_0 was portrait and
2) Only set a preference when an activity was compiled for sensor-based
  orientations.

This change fixes the ROTATE_0 assumption and provides a PORTRAIT
preference in VR mode for all activities that aren't explicitly
set screenOrientation to "portrait" or "landscape".

Bug: 63289312, 62862109
Test: In VR Mode, tested activity preferences of sensor, unspecified,
portrait and landscape both on the main display and the virtual display.

Change-Id: Ifa04cbcd021e2d744ff70e53cd53359b1ddf5877
1 file changed