Open permission manager service to the world

There are many permission related APIs currently handled by the
package manager service. These are simply pass throughs from the
package manager service to an internal API defined by the
permission manager service. Instead of this multi-hop, we want
to open the permission manager service directly to apps. For
legacy, we won't be able to remove the APIs from PackageManager,
but, the implementation should go directly to the Permission
Manager Service.

Test: System boots w/o selinux denials
Change-Id: I1d953077b3da18ccf44deb85b9084be68a2179bd