DO NOT MERGE: Neverallow isolated and untrusted apps to write system properties

and as a consequence open up for other appdomains (e.g. platform_app)
to write system properties.

(cherrypicked from commit 0d8e9adf49a1db942ad3c556d87d25bde94e0df5)
Change-Id: Ie6ad4d17247165564456e5b0d78f705a82cdcde7
3 files changed