NetdBinderTest.TetherOffloadForwarding - cleanup stats post test

This additionally allows us to check that statistics are correct.

Test: atest netd_integration_test:NetdBinderTest#TetherOffloadForwarding
Bug: 150736748
Original-Change: https://android-review.googlesource.com/1328674
Merged-In: I15a2a9d78ab9d3b5773375a2bd31cb1b2f678c4a
Change-Id: I15a2a9d78ab9d3b5773375a2bd31cb1b2f678c4a
diff --git a/tests/binder_test.cpp b/tests/binder_test.cpp
index f3667b9..2a6bb7c 100644
--- a/tests/binder_test.cpp
+++ b/tests/binder_test.cpp
@@ -3735,6 +3735,16 @@
 
     // Clean up.
     EXPECT_TRUE(mNetd->tetherOffloadRuleRemove(rule).isOk());
+
+    TetherStatsParcel tetherStats;
+    EXPECT_TRUE(mNetd->tetherOffloadGetAndClearStats(sTun.ifindex(), &tetherStats).isOk());
+    EXPECT_EQ("", tetherStats.iface);
+    EXPECT_EQ(static_cast<int64_t>(sizeof(pkt)), tetherStats.rxBytes);
+    EXPECT_EQ(1, tetherStats.rxPackets);
+    EXPECT_EQ(0, tetherStats.txBytes);
+    EXPECT_EQ(0, tetherStats.txPackets);
+    EXPECT_EQ(sTun.ifindex(), tetherStats.ifIndex);
+
     EXPECT_TRUE(mNetd->ipfwdRemoveInterfaceForward(tap.name(), sTun.name()).isOk());
     EXPECT_TRUE(mNetd->tetherRemoveForward(tap.name(), sTun.name()).isOk());
     EXPECT_TRUE(mNetd->networkRemoveRoute(INetd::LOCAL_NET_ID, tap.name(), kDownstreamPrefix, "")