docs: public boolean track()
      {
          byte[] imageData = getImageData();
          if (imageData == null)
          {
              return false;
          }
          if (trackFromImage(imageData))
          {
              getGVRContext().getEventManager().sendEvent(this, TrackerEvents.class, "onTrackUpdate", this);
              return updateSkeleton();
          }
          return false;
      }