Notify users when admin grants location permission

When the admin grants a location-related permission to an app (using
DevicePolicyManager.setPermissionGrantState), notify the user that the
app got this permission.

Implementation: The AutoGrantPermissionsNotifier introduced in a
previous change is used to present the notification to the user.

In PermissionControllerServiceImpl.onSetRuntimePermissionGrantStateByDeviceAdmin,
when the permission is actually granted to the app, each permission is
logged. Before the method returns,
AutoGrantPermissionsNotifier.notifyOfAutoGrantPermissions method is called,
which issues the notification.

Tapping the notification sends the user to the Settings screen where app
permissions can be seen (but not controlled).

Note that this notification does vibrate and emit a sound, while the
notification shown for permissions granted via policy do not, as the
latter notification is shown in-context, when the app requests (and is
granted) the permission.

Testing:
* Install TestDPC.
* Set TestDPC as Device Owner
* Get the BasicLocation app by checking out
https://github.com/android/location-samples and building it from there.
* Install the app onto the device but do not start it.
* Find "Manage app permissions", choose "Basic Location Sample" from the
drop-down menu.
* Toggle each of the "ACCESS_COARSE_LOCATION" and
"ACCESS_BACKGROUND_LOCATION" to "Allow".
* Observe notification

Bug: 148631522
Test: Manual, see above
Change-Id: I4fef2d5d47718265bec6aaf9b485e86b9da91ec3