Revert "PrivacyGuard: add missing @hides to method definitions"

This reverts commit a18c654b4fb87dd4d05a43bfe1897011b23350fc.
Revert "Privacy Guard : Reimplement backed by AppOps"

This reverts commit a646c5527fb3da70fb3297099c28fed2bf4871b2.

Conflicts:
	core/java/android/provider/Settings.java
	core/res/res/drawable-hdpi/stat_notify_privacy_guard.png
	core/res/res/drawable-mdpi/stat_notify_privacy_guard.png
	core/res/res/drawable-xhdpi/stat_notify_privacy_guard.png
	core/res/res/drawable-xxhdpi/stat_notify_privacy_guard.png

Change-Id: Ifa6c1019c4a894cc4f2371e062322c11574840bd