AtomicLong count = (nameFormat != null) ? new AtomicLong(0) : null;
    return new ThreadFactory() {
      @Override
      public Thread newThread(Runnable runnable) {
        Thread thread = backingThreadFactory.newThread(runnable);
        // TODO(b/139735208): Figure out what to do when the factory returns null.
        requireNonNull(thread);
        if (nameFormat != null) {