Second patch in making destructors of refcounted objects private.

net/http/http_network_session.h

Index: net/http/http_network_session.h
===================================================================
--- net/http/http_network_session.h	(revision 31079)
+++ net/http/http_network_session.h	(working copy)
@@ -25,7 +25,6 @@
                      ClientSocketFactory* client_socket_factory,
                      SSLConfigService* ssl_config_service,
                      FlipSessionPool* flip_session_pool);
-  ~HttpNetworkSession();
 
   HttpAuthCache* auth_cache() { return &auth_cache_; }
   SSLClientAuthCache* ssl_client_auth_cache() {
@@ -44,8 +43,11 @@
   static void set_max_sockets_per_group(int socket_count);
 
  private:
+  friend class base::RefCounted<HttpNetworkSession>;
   FRIEND_TEST(HttpNetworkTransactionTest, GroupNameForProxyConnections);
 
+  ~HttpNetworkSession();
+
   // Total limit of sockets. Not a constant to allow experiments.
   static int max_sockets_;