Add net-utils-annotations lib

- Move PolicyDirection into frameworks/libs/net
- Add net-utils-annotations lib for those methods that are using
  PolicyDirection annotation.
- Add net-utils-annotations-srcs for including PolicyDirection to
  their filegroup.

Bug: 203634639
Test: m
Change-Id: I7b8b3bdcc3be5fca9baa5a9ce656756843e03527
diff --git a/staticlibs/Android.bp b/staticlibs/Android.bp
index a7a027c..4be2fca 100644
--- a/staticlibs/Android.bp
+++ b/staticlibs/Android.bp
@@ -229,3 +229,30 @@
         "//packages/modules/Wifi/service",
     ],
 }
+
+// This file group is deprecated; new users should use net-utils-annotations
+filegroup {
+    name: "net-utils-annotations-srcs",
+    srcs: [
+        "annotations/android/net/annotations/PolicyDirection.java",
+    ],
+    visibility: [
+        "//frameworks/base",
+    ],
+}
+
+
+java_library {
+    name: "net-utils-annotations",
+    srcs: [":net-utils-annotations-srcs"],
+    libs: [
+        "framework-annotations-lib",
+    ],
+    sdk_version: "system_current",
+    min_sdk_version: "30",
+    visibility: ["//visibility:public"],
+    apex_available: [
+        "//apex_available:anyapex",
+        "//apex_available:platform",
+    ],
+}