Zen upgrade notification

Test: runtest --path /extra/master/frameworks/base/services/tests/uiservicestests/src/com/android/server/notification/ZenModeHelperTest.java
Change-Id: Ia31f89af74d9bcee40e050bd6cc13f1e6a9a15d9
Fixes: 73000503
Fixes: 72876890
Fixes: 73110052
diff --git a/proto/src/system_messages.proto b/proto/src/system_messages.proto
index 08fdb97..608970f 100644
--- a/proto/src/system_messages.proto
+++ b/proto/src/system_messages.proto
@@ -204,6 +204,10 @@
     // Package: android
     NOTE_USB_TETHER = 47;
 
+    // Inform that DND settings have changed on OS upgrade
+    // Package: android
+    NOTE_ZEN_UPGRADE = 48;
+
     // ADD_NEW_IDS_ABOVE_THIS_LINE
     // Legacy IDs with arbitrary values appear below
     // Legacy IDs existed as stable non-conflicting constants prior to the O release
@@ -253,6 +257,7 @@
 
     // Notify the user about public volume state changes..
     // Package: com.android.systemui
+
     NOTE_STORAGE_PUBLIC = 0x53505542;  // 1397773634
 
     // Notify the user about private volume state changes.