Merge "Refactor to SimChangeListener class"

diff --cc services/core/java/com/android/server/connectivity/Tethering.java
index de17740,df169e9..bd88ddb
--- 1/services/core/java/com/android/server/connectivity/Tethering.java
--- 2/services/core/java/com/android/server/connectivity/Tethering.java
+++ b/services/core/java/com/android/server/connectivity/Tethering.java
@@@ -1487,9 -1522,9 +1518,9 @@@ public class Tethering extends BaseNetw
  
              @Override
              public void exit() {
 -                turnOffUpstreamMobileConnection();
 +                unrequestUpstreamMobileConnection();
                  mUpstreamNetworkMonitor.stop();
-                 stopListeningForSimChanges();
+                 simChange.stopListening();
                  notifyTetheredOfNewUpstreamIface(null);
                  handleNewUpstreamNetworkState(null);
              }