VPN: silence VPN notifications.

Bug: 5852859
Change-Id: I269d8de298a1fd69a8d777150ae97927537a5424
diff --git a/services/java/com/android/server/connectivity/Vpn.java b/services/java/com/android/server/connectivity/Vpn.java
index 72cf512..a76e70f 100644
--- a/services/java/com/android/server/connectivity/Vpn.java
+++ b/services/java/com/android/server/connectivity/Vpn.java
@@ -322,7 +322,7 @@
                     .setContentTitle(title)
                     .setContentText(text)
                     .setContentIntent(VpnConfig.getIntentForStatusPanel(mContext, config))
-                    .setDefaults(Notification.DEFAULT_ALL)
+                    .setDefaults(0)
                     .setOngoing(true)
                     .getNotification();
             nm.notify(R.drawable.vpn_connected, notification);