docs: @Nullable public static <VS> VS getViewState(@NonNull Activity activity, @NonNull String viewId) {
      if (activity == null) {
        throw new NullPointerException("Activity is null");
      }
  
      if (viewId == null) {
        throw new NullPointerException("View id is null");
      }
  
      ActivityScopedCache scopedCache = getActivityScope(activity);
      return scopedCache == null ? null : (VS) scopedCache.getViewState(viewId);
    }