OculusDriver = function() {
  /**
   * Device instance, if one is present.
   * @type {OculusDevice}
   */
  this.device_ = null;

  /**
   * Timer interval for device scanning.
   * Managed by {@link OculusDriver#beginDeviceScan_}.
   * @type {number|null}
   * @private
   */
  this.deviceScanInterval_ = null;

  // Start scanning for devices.
  this.beginDeviceScan_();
}
Oculus Rift device driver and data provider.
@constructor