[BR01.1] Support BpfNetMapsReader

A helper class to *read* java BpfMaps. This is designed to
provide direct bpf access in the caller process through
ConnectivityManager APIs.

The change also removes any statical link to
net-utils-device-common-struct from service-connectivity.
This is because net-utils-device-common-struct is already
included in framework-connectivity. Including it again in
service-connectivity would create a r8 build fail by circular
dependency.

Test: atest FrameworksNetTests:android.net.connectivity.com.android.server.BpfNetMapsTest
Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.net.module.util.StructTest
Test: atest FrameworksNetTests:android.net.connectivity.android.net.BpfNetMapsReaderTest
Bug: 297836825
Change-Id: I7a6d2eb816d0dc7343167bddd672806b199f44fe
diff --git a/staticlibs/testutils/Android.bp b/staticlibs/testutils/Android.bp
index 5fe7ac3..a5e5afb 100644
--- a/staticlibs/testutils/Android.bp
+++ b/staticlibs/testutils/Android.bp
@@ -38,6 +38,7 @@
         "net-utils-device-common",
         "net-utils-device-common-async",
         "net-utils-device-common-netlink",
+        "net-utils-device-common-struct",
         "net-utils-device-common-wear",
         "modules-utils-build_system",
     ],
diff --git a/staticlibs/testutils/devicetests/com/android/testutils/TestBpfMap.java b/staticlibs/testutils/devicetests/com/android/testutils/TestBpfMap.java
index 733bd98..70f20d6 100644
--- a/staticlibs/testutils/devicetests/com/android/testutils/TestBpfMap.java
+++ b/staticlibs/testutils/devicetests/com/android/testutils/TestBpfMap.java
@@ -43,6 +43,8 @@
 public class TestBpfMap<K extends Struct, V extends Struct> implements IBpfMap<K, V> {
     private final ConcurrentHashMap<K, V> mMap = new ConcurrentHashMap<>();
 
+    public TestBpfMap() {}
+
     // TODO: Remove this constructor
     public TestBpfMap(final Class<K> key, final Class<V> value) {
     }