Steps to reproduce:
1. Download and open the attached project
2. Make sure you have a headset and controllers c
2. Enter Playmode

Expected result: Logs for HardwareTracker output real values
Actual result: HardwareTracker values are always 0

Reproduced on 2017.2.0b1, 2017.2.0p1, 2017.3.0b9, 2018.1.0a3
Feature introduced in 2017.2

Dev notes:

Updated documentation in changeset cc1c900032d6 for 2018.2.

It still won't actually return a value for the Hardware Tracker, but this is by design. I added documentation and a warning in the console that explains that GameController, TrackingReference, and HardwareTracker XRNode types are not singleton nodes (there could be multiple of them), and so you need to use InputTracking.GetNodeStates to get data on them. GetLocalPosition/Rotation is to be used with nodes that there can be only 1 of (Left Eye, Left Hand, Head, etc..) because there is no way to indicate which actual node you want on these older APIs.