Make PermissionControllerManager user aware

Most of the commands of PermissionControllerManager should go to the
calling user. If not - and the alternate user is running - we should
use the recommended way to talk to alternate users. This recommended way
is to create a package context for the user and call the method on this
new context.

Hence
- At a time we can have more than one RemoteService (one per user)
- Connect to the user declared in Context#getUser instead of the calling
user

Test: Called methods on work-profiles and saw alternate
PermissionController apps to be spawned.
Change-Id: I9ed87db1f658f18b69d19b39ba9f96361ec5af82