Add back "default address family" to HostResolver

net/dns/host_resolver.cc

Index: net/dns/host_resolver.cc
diff --git a/net/dns/host_resolver.cc b/net/dns/host_resolver.cc
index df958933d79aaff66735c840918da0e890d77618..f0cd91b5787267edf28c757e4cb80929e0480f1e 100644
--- a/net/dns/host_resolver.cc
+++ b/net/dns/host_resolver.cc
@@ -132,6 +132,14 @@ void HostResolver::InitializePersistence(
     const PersistCallback& persist_callback,
     std::unique_ptr<const base::Value> old_data) {}
 
+void HostResolver::SetDefaultAddressFamily(AddressFamily address_family) {
+  NOTREACHED();
+}
+
+AddressFamily HostResolver::GetDefaultAddressFamily() const {
+  return ADDRESS_FAMILY_UNSPECIFIED;
+}
+
 // static
 std::unique_ptr<HostResolver> HostResolver::CreateSystemResolver(
     const Options& options,