HarmonyOS 获取系统相册中图片数量和时间相册中不符合。

代码：

let frSys = await this.phAccessHelper!.getAlbums(photoAccessHelper.AlbumType.SYSTEM, photoAccessHelper.AlbumSubtype.ANY);
let predicates: dataSharePredicates.DataSharePredicates = new dataSharePredicates.DataSharePredicates();
let fetchOption: photoAccessHelper.FetchOptions = {
  fetchColumns: [],
  predicates: predicates
};
if(frSys != undefined){
  let al = await frSys.getAllObjects();
  for (let album of al) {
    let  p: Map<string, Object> = new Map();
    p.set("albumId", album.albumUri);
    p.set("albumName", album.albumName);
    p.set("count", album.count);
    p.set("thumbPath",album.coverUri);
    p.set("thumbIdentifier", "");
    let albumFetchResult =  await album.getAssets(fetchOption);
    if(albumFetchResult != undefined){
      console.info('album getAssets successfully, getCount: ' + albumFetchResult.getCount());
    }
    albumList.push(p);
  }
  frSys.close();
}

其中得到的数量都是0，系统相册数量是8。获取用户相册正常。（photoAccessHelper.AlbumType.USER）