Make data warning notification heads up.

Bug: 30760683
Change-Id: Id3fed0a62936dddabcb169536a4a917d750259d7
diff --git a/services/core/java/com/android/server/net/NetworkPolicyManagerService.java b/services/core/java/com/android/server/net/NetworkPolicyManagerService.java
index 8f9cc47..da615ec 100644
--- a/services/core/java/com/android/server/net/NetworkPolicyManagerService.java
+++ b/services/core/java/com/android/server/net/NetworkPolicyManagerService.java
@@ -1074,6 +1074,8 @@
                 builder.setTicker(title);
                 builder.setContentTitle(title);
                 builder.setContentText(body);
+                builder.setDefaults(Notification.DEFAULT_ALL);
+                builder.setPriority(Notification.PRIORITY_HIGH);
 
                 final Intent snoozeIntent = buildSnoozeWarningIntent(policy.template);
                 builder.setDeleteIntent(PendingIntent.getBroadcast(