Add a histogram to measure the number of idle sockets when a TCP connection is established.

net/base/client_socket_handle.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_BASE_CLIENT_SOCKET_HANDLE_H_
 #define NET_BASE_CLIENT_SOCKET_HANDLE_H_
 
 #include <string>
 
 #include "base/ref_counted.h"
@@ skipping 44 matching lines @@
   //
   // NOTE: To prevent the socket from being kept alive, be sure to call its
   // Disconnect method.
   //
   void Reset();
 
   // Returns true when Init has completed successfully.
   bool is_initialized() const { return socket_ != NULL; }
 
   // These may only be used if is_initialized() is true.
+  const std::string& group_name() const { return group_name_; }
   ClientSocket* socket() { return socket_->get(); }
   ClientSocket* release_socket() { return socket_->release(); }
   void set_socket(ClientSocket* s) { socket_->reset(s); }
 
  private:
   friend class ClientSocketPool;
 
   scoped_refptr<ClientSocketPool> pool_;
   scoped_ptr<ClientSocket>* socket_;
   std::string group_name_;
 
   DISALLOW_COPY_AND_ASSIGN(ClientSocketHandle);
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_CLIENT_SOCKET_HANDLE_H_