Switch LoadTimeStatsTabHelper to use WebContentsUserData.

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>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/hash_tables.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/time.h"
 #include "chrome/browser/net/chrome_url_request_context.h"
+#include "chrome/browser/tab_contents/web_contents_user_data.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "net/base/network_delegate.h"
 
-class TabContents;
-
 namespace base {
 class Histogram;
 }
 
 namespace net {
 class URLRequest;
 class URLRequestContext;
 }
 
 #if defined(COMPILER_GCC)
@@ skipping 78 matching lines @@
                         bool is_load_done);
 
   TabLoadStatsMap tab_load_stats_;
   RequestStatsMap request_stats_;
   std::vector<base::Histogram*> histograms_[REQUEST_STATUS_MAX][HISTOGRAM_MAX];
   base::hash_set<const net::URLRequestContext*> main_request_contexts_;
 
   DISALLOW_COPY_AND_ASSIGN(LoadTimeStats);
 };
 
-// A WebContentsObserver watching all tabs, notifying LoadTimeStats
-// whenever the spinner starts or stops for a given tab, and when a renderer
-// is no longer used.
-class LoadTimeStatsTabHelper : public content::WebContentsObserver {
+// A WebContentsObserver watching a tab, notifying LoadTimeStats whenever the
+// spinner starts or stops for it, and whenever a renderer is no longer used.
+class LoadTimeStatsTabHelper
+    : public content::WebContentsObserver,
+      public WebContentsUserData<LoadTimeStatsTabHelper> {
  public:
-  explicit LoadTimeStatsTabHelper(TabContents* tab);
   virtual ~LoadTimeStatsTabHelper();
 
   // content::WebContentsObserver implementation
   virtual void DidStartProvisionalLoadForFrame(
       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);
+                           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_