Add Data Saver utils in Firewall test helper class

Resolv_integration_test needs the function to toggle Data Saver settings
in BPF map.

Bug: 288340533
Test: atest resolv_integration_test
Change-Id: I1725d3c8c6fc641b855c935d7289a99f78dd5933
diff --git a/tests/native/utilities/firewall.h b/tests/native/utilities/firewall.h
index 1e7e987..b3d69bf 100644
--- a/tests/native/utilities/firewall.h
+++ b/tests/native/utilities/firewall.h
@@ -33,9 +33,11 @@
     Result<void> removeRule(uint32_t uid, UidOwnerMatchType match) EXCLUDES(mMutex);
     Result<void> addUidInterfaceRules(const std::string& ifName, const std::vector<int32_t>& uids);
     Result<void> removeUidInterfaceRules(const std::vector<int32_t>& uids);
-
+    Result<bool> getDataSaverSetting();
+    Result<void> setDataSaver(bool enabled);
   private:
     BpfMap<uint32_t, uint32_t> mConfigurationMap GUARDED_BY(mMutex);
     BpfMap<uint32_t, UidOwnerValue> mUidOwnerMap GUARDED_BY(mMutex);
+    BpfMap<uint32_t, bool> mDataSaverEnabledMap GUARDED_BY(mMutex);
     std::mutex mMutex;
 };