docs: @Nullable @MainThread static ActivityScopedCache getActivityScope(@NonNull Activity activity) {
      if (activity == null) {
        throw new NullPointerException("Activity is null");
      }
      String activityId = activityIdMap.get(activity);
      if (activityId == null) {
        return null;
      }
  
      return activityScopedCacheMap.get(activityId);
    }