Support java BpfMap in BpfNetMaps#swapActiveStatsMap

Bug: 217624062
Test: atest BpfNetMapsTest
android.net.cts.NetworkStatsManagerTest
android.net.cts.TrafficStatsTest

Change-Id: I9cb673673d2ed1dda8fa14c0877e2fc683267791
diff --git a/service/jni/com_android_server_BpfNetMaps.cpp b/service/jni/com_android_server_BpfNetMaps.cpp
index 11ba235..71fa8e4 100644
--- a/service/jni/com_android_server_BpfNetMaps.cpp
+++ b/service/jni/com_android_server_BpfNetMaps.cpp
@@ -191,6 +191,10 @@
     mTc.dump(fd, verbose);
 }
 
+static jint native_synchronizeKernelRCU(JNIEnv* env, jobject self) {
+    return -bpf::synchronizeKernelRCU();
+}
+
 /*
  * JNI registration.
  */
@@ -225,6 +229,8 @@
     (void*)native_setPermissionForUids},
     {"native_dump", "(Ljava/io/FileDescriptor;Z)V",
     (void*)native_dump},
+    {"native_synchronizeKernelRCU", "()I",
+    (void*)native_synchronizeKernelRCU},
 };
 // clang-format on