filebrowser: don't treat readonly folders as a different kind from folders
filebrowser: don't treat readonly folders as a different kind from folders

lucius-feng/seafile-client,wgaalves/seafile-client,losingle/seafile-client,wgaalves/seafile-client,daodaoliang/seafile-client,wgaalves/seafile-client,haiwen/seafile-client,haiwen/seafile-client,losingle/seafile-client,lucius-feng/seafile-client,losingle/seafile-client,daodaoliang/seafile-client,haiwen/seafile-client,lucius-feng/seafile-client,haiwen/seafile-client,wgaalves/seafile-client,lucius-feng/seafile-client,losingle/seafile-client,daodaoliang/seafile-client,daodaoliang/seafile-client