Add user control to turn on/off nsd

Change-Id: Ide3cc20adb21ac6dffaf6b9b9136d77a129afa3b
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 6dfbb2f..3a5fdd1 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -3277,6 +3277,12 @@
             "wifi_mobile_data_transition_wakelock_timeout_ms";
 
         /**
+         * Whether network service discovery is enabled.
+         * @hide
+         */
+        public static final String NSD_ON = "nsd_on";
+
+        /**
          * Whether background data usage is allowed by the user. See
          * ConnectivityManager for more info.
          */