Add @SystemApi to related VR functions that will be used by VrCore
Services.

We added them to grey list, but it would be better to make them proper
SystemApi.

Bug: 74430927
Test: Run VR app, not seeing VR related "Accessing hidden field" log.

Change-Id: I9e6ec7eb35244fbac4f6448721458efbee65a887
8 files changed