framework: Privacy Guard

 * Introduce a new privacy feature which allows the user to run an
   application with reduced visibility into his or her personal data.
 * Adds a per-application flag and simple API to determine if this flag
   is enabled for the current or calling process.
 * This flag can be used by content providers to decide if they should
   return a limited/empty dataset.

Patchset: fix notification behaviour
PatchSet: fix possible NPE on clean install if data apps are pushed
	  from gapps eg.
PatchSet: add back deleted 5 lines...thanks jeff
PatchSet: fix call for not allowed userState -1
PatchSet: check against userId and not identifier
PatchSet: fix for real now lol

Change-Id: Id7c54d728e63acb2b02a2a9322930b54949f6c5d