[NETD-TC#10] Create BpfNetMaps class

BpfNetMaps provide interfaces and native methods for
manipulating BPF maps by calling jni library of traffic controller.

DO NOT TOUCH BpfNetMaps before aosp/1945136 and aosp/1948169 get merged.

Bug: 202086915
Test: build and flash
Change-Id: Iaff8ac71100b3f76b444f3b83616556d0ee6eadf
diff --git a/service/Android.bp b/service/Android.bp
index 5ba6a00..e376ff7 100644
--- a/service/Android.bp
+++ b/service/Android.bp
@@ -162,3 +162,11 @@
     srcs: ["jarjar-rules.txt"],
     visibility: ["//packages/modules/Connectivity:__subpackages__"],
 }
+
+// TODO: This filegroup temporary exposes for NetworkStats. It should be
+// removed right after NetworkStats moves into mainline module.
+filegroup {
+    name: "traffic-controller-utils",
+    srcs: ["src/com/android/server/BpfNetMaps.java"],
+    visibility: ["//packages/modules/Connectivity:__subpackages__"],
+}