Summary:
The Android version of PlatformConstants exposes the device's [UI Mode]( https://developer.android.com/guide/topics/resources/providing-resources#UiModeQualifier). It is missing the case for 'vrheadset', added in Android API 26. We should return the expected result when this is queried.
Changelog:
[Android][Added] - Expose UI_MODE_TYPE_VR_HEADSET in PlatformConstants
Reviewed By: rshest
Differential Revision: D38495875
fbshipit-source-id: fd904bd11213448415b7d75145d9ba6311ed407b