Make using WebContentsUserData simpler.

chrome/browser/net/load_time_stats.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_LOAD_TIME_STATS_H_
 #define CHROME_BROWSER_NET_LOAD_TIME_STATS_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 119 matching lines @@
       int64 frame_id,
       bool is_main_frame,
       const GURL& validated_url,
       bool is_error_page,
       content::RenderViewHost* render_view_host) OVERRIDE;
   virtual void DidStopLoading(
       content::RenderViewHost* render_view_host) OVERRIDE;
 
  private:
   explicit LoadTimeStatsTabHelper(content::WebContents* web_contents);
-  static int kUserDataKey;
   friend class WebContentsUserData<LoadTimeStatsTabHelper>;
 
   // Calls into LoadTimeStats to notify that a reportable event has occurred
   // for the tab being observed.
   void NotifyLoadTimeStats(LoadTimeStats::TabEvent event,
                            content::RenderViewHost* render_view_host);
 
   bool is_otr_profile_;
 
   DISALLOW_COPY_AND_ASSIGN(LoadTimeStatsTabHelper);
 };
 
 }  // namespace chrome_browser_net
 
 #endif  // CHROME_BROWSER_NET_LOAD_TIME_STATS_H_