do not unregister event when app goes to background.

since VoIP app switch focosed activity oftenly
we should allow incall manager to manage audio route during background
and incall manager's life cycle should controled by app logic

Author: zxcpoiu

android/src/main/java/com/zxcpoiu/incallmanager/InCallManagerModule.java

@@ -1656,13 +1656,13 @@ protected static void onRequestPermissionsResult(int requestCode, String[] permi
     @Override
     public void onHostResume() {
         Log.d(TAG, "onResume()");
-        resume();
+        //resume();
     }
 
     @Override
     public void onHostPause() {
         Log.d(TAG, "onPause()");
-        pause();
+        //pause();
     }
 
     @Override