libselinux has special handling for the app data directories such as
/data/user/$userId/$pkgName and /data/user_de/$userId/$pkgName, because
their SELinux contexts are determined differently from "normal" files.
/data/storage_area/$userId/$pkgName will be a new app data directory
(with a different SELinux context, but determined through the same process).
THerefore, add it to the list of app data directories.
Bug: 325129836
Change-Id: I4371c23193e6ad07207bc1f22cfd6d1580ccd600
261afd394b