Revert^2 "Mark @FlaggedApi flags as exported"

322dd88f9dedd580115bd62377c2a21323540d2f

Change-Id: I9d1b06d9bea270e22f364bbc4be24174d3ae53fe
diff --git a/services/backup/flags.aconfig b/services/backup/flags.aconfig
index 9326ea8..b4adad2 100644
--- a/services/backup/flags.aconfig
+++ b/services/backup/flags.aconfig
@@ -68,6 +68,7 @@
             "B&R operations in certain cases."
     bug: "376661510"
     is_fixed_read_only: true
+    is_exported: true
 }
 
 flag {