Add java_defaults for @FlaggedApi handling

This CL is a preparation to ignore @FlaggedApi API in udc mainline
branch

Bug: 299411828
Test: TH
Change-Id: If3217916b2c37ebaa7b48d8387c69cb078af9550
diff --git a/Tethering/common/TetheringLib/Android.bp b/Tethering/common/TetheringLib/Android.bp
index a4db776..975ca08 100644
--- a/Tethering/common/TetheringLib/Android.bp
+++ b/Tethering/common/TetheringLib/Android.bp
@@ -21,6 +21,7 @@
     name: "framework-tethering",
     defaults: [
         "framework-tethering-defaults",
+        "FlaggedApiDefaults",
     ],
     impl_library_visibility: [
         "//packages/modules/Connectivity/Tethering:__subpackages__",