Add contacts aggregation event to the log.
diff --git a/logcat/event-log-tags b/logcat/event-log-tags
index b5386d3..4db86cb 100644
--- a/logcat/event-log-tags
+++ b/logcat/event-log-tags
@@ -82,6 +82,10 @@
# disk space free on the /data partition in bytes
2746 free_storage_left (data|2|2)
+# contacts aggregation: time and number of contacts.
+# count is negative for query phase, positive for merge phase
+2747 contacts_aggregation (aggregation time|2|3), (count|1|1)
+
# when a NotificationManager.notify is called
2750 notification_enqueue (pkg|3),(id|1|5),(notification|3)
# when someone tries to cancel a notification, the notification manager sometimes