Make activities that are in VR mode ignore ui mode config changes.

Going into VR UI mode, when in VR mode, will not cause an activity recreate
on pre-O apps.

Bug: 30989383,34849643
Test: ran vr mode activity, checked dumpsys uimode for correct values
Change-Id: I0d371cce4920dbf2bdeb84dc6c741d12fc2ce444
1 file changed