clang: Fix several -Woverloaded-virtual warnings.

net/http/http_network_transaction_unittest.cc

Index: net/http/http_network_transaction_unittest.cc
diff --git a/net/http/http_network_transaction_unittest.cc b/net/http/http_network_transaction_unittest.cc
index 8ac2a6ed232c98b5ff4ac45405d084d2eb7618f3..8c87136c17fc1b4ef4f6e1bc8a9b813874237071 100644
--- a/net/http/http_network_transaction_unittest.cc
+++ b/net/http/http_network_transaction_unittest.cc
@@ -271,7 +271,8 @@ class CaptureGroupNameSocketPool : public ParentPool {
   virtual void CancelRequest(const std::string& group_name,
                              ClientSocketHandle* handle) {}
   virtual void ReleaseSocket(const std::string& group_name,
-                             ClientSocket* socket) {}
+                             ClientSocket* socket,
+                             int id) {}
   virtual void CloseIdleSockets() {}
   virtual int IdleSocketCount() const {
     return 0;