Add a bugfix feature for roaming notification

This feature works if carrier only allows a single data network,
Telephony will wait until the Internet connection is completely
disconnected and then update roaming notifications once again to
check if the disallow reasons for single data network has gone away.

Bug: 249908996
Test: manually tested in roaming network with config override.
Change-Id: I6e4ea323250e09406a040067b4f842f301518e5b
diff --git a/flags/misc.aconfig b/flags/misc.aconfig
index f5e9f6f..d7bed88 100644
--- a/flags/misc.aconfig
+++ b/flags/misc.aconfig
@@ -116,3 +116,14 @@
         purpose: PURPOSE_BUGFIX
     }
 }
+
+# OWNER=sangyun TARGET=24Q3
+flag {
+    name: "roaming_notification_for_single_data_network"
+    namespace: "telephony"
+    description: "Fix bug where roaming notification was not shown on a single data network."
+    bug:"249908996"
+    metadata {
+        purpose: PURPOSE_BUGFIX
+    }
+}
\ No newline at end of file