Add the UMA recording recall of URLRequests preconnected.

chrome/browser/net/chrome_network_delegate.h

 // Copyright (c) 2012 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 CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_
 #define CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 102 matching lines @@
   static Value* HistoricNetworkStatsInfoToValue();
 
   // Creates a Value summary of the state of the network session. The caller is
   // responsible for deleting the returned value.
   Value* SessionNetworkStatsInfoToValue() const;
 
  private:
   friend class ChromeNetworkDelegateTest;
 
   // NetworkDelegate implementation.
+  virtual void OnBeforePreconnect(const GURL& url) OVERRIDE;
   virtual int OnBeforeURLRequest(net::URLRequest* request,
                                  const net::CompletionCallback& callback,
                                  GURL* new_url) OVERRIDE;
   virtual int OnBeforeSendHeaders(net::URLRequest* request,
                                   const net::CompletionCallback& callback,
                                   net::HttpRequestHeaders* headers) OVERRIDE;
   virtual void OnSendHeaders(net::URLRequest* request,
                              const net::HttpRequestHeaders& headers) OVERRIDE;
   virtual int OnHeadersReceived(
       net::URLRequest* request,
@@ skipping 70 matching lines @@
   // over the network.
   int64 received_content_length_;
 
   // Total original size of all content before it was transferred.
   int64 original_content_length_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeNetworkDelegate);
 };
 
 #endif  // CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_