Do DNS64 prefix discovery in netd

Test: as follows
    - built, flashed, booted
    - system/netd/tests/runtests.sh passes
    - dumpsys netd observes DNS64 discovery output
Bug: 78545619
Change-Id: I447c35229b07e8077546a03489d36e7be9d969a3
diff --git a/server/ResolverController.h b/server/ResolverController.h
index 287e199..375c7da 100644
--- a/server/ResolverController.h
+++ b/server/ResolverController.h
@@ -19,9 +19,9 @@
 
 #include <list>
 #include <vector>
+#include "dns/Dns64Configuration.h"
 
 struct __res_params;
-struct sockaddr_storage;
 
 namespace android {
 namespace net {
@@ -38,10 +38,10 @@
 
 
 class ResolverController {
-public:
-    ResolverController() {};
+  public:
+    ResolverController(const NetworkController& netCtrl) : mDns64Configuration(netCtrl) {}
 
-    virtual ~ResolverController() {};
+    ~ResolverController() {}
 
     // TODO: delete this function
     int setDnsServers(unsigned netId, const char* searchDomains, const char** servers,
@@ -82,6 +82,8 @@
 
     void dump(DumpWriter& dw, unsigned netId);
 
+  private:
+    Dns64Configuration mDns64Configuration;
 };
 
 }  // namespace net