private void addTrackingHeaders(HttpHeaders httpHeaders) {
    for (String header : RestUtils.TrackingHeaders.TRACKING_HEADERS) {
      httpHeaders.set(header, header);
    }
  }
Add tracking headers to the {@link HttpHeaders}
@param httpHeaders the {@link HttpHeaders} to be added with tracking headers
ambry-rest/src/test/java/com/github/ambry/rest/NettyResponseChannelTest.java