webkitGetAsEntry.createReader.readEntries does not include symlinks

1. prepare a folder which contains at least one or more valid symlinks (with destinations either within or outside the folder), for example: `ln -s ../pic.jpg .`
2. access https://ocv.me/stuff/bugs/chrome/filedrop-symlinks.html
3. drag/drop the folder into the browser

Only the regular directories and files will be passed to the readEntries callback; the symlinks are ignored

* This works fine on firefox 99
* Does not work on chrome 83, 100/stable, 103/canary
* Same behavior on Debian 11, Alpine 3.15, Arch
* Same behavior on Xfce, KDE, Gnome
* Symlink destination does not matter (within or outside the folder)