telephony: Make "Do not ask again" functional

* When on WiFi I get a notification telling me emergency services are
  not available with a "Do not ask again" button. This button is not
  functional, thus I am being asked again all the time
* Exporting the receiver finally makes the notification disappear

Change-Id: I32408f08e7c6e29e5fc8b6386129e4f897fd761a