Refactor RenderWidgetHost::set_paint_observer()

chrome/browser/dom_ui/new_tab_ui.h

 // Copyright (c) 2010 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_DOM_UI_NEW_TAB_UI_H_
 #define CHROME_BROWSER_DOM_UI_NEW_TAB_UI_H_
 #pragma once
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
+#include "base/timer.h"
 #include "chrome/browser/dom_ui/dom_ui.h"
 #include "chrome/browser/dom_ui/chrome_url_data_manager.h"
 #include "chrome/browser/sessions/tab_restore_service.h"
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_registrar.h"
 
 class GURL;
 class MessageLoop;
 class PrefService;
 class Profile;
@@ skipping 59 matching lines @@
     static bool first_run_;
 
     // Pointer back to the original profile.
     Profile* profile_;
 
     DISALLOW_COPY_AND_ASSIGN(NewTabHTMLSource);
   };
 
  private:
   FRIEND_TEST_ALL_PREFIXES(NewTabUITest, UpdateUserPrefsVersion);
+  class PaintTimer : public NotificationObserver {
+   public:
+    PaintTimer(RenderViewHost* render_view_host);
+
+   private:
+    void Timeout();
+    virtual void Observe(NotificationType type,
+                         const NotificationSource& source,
+                         const NotificationDetails& details);
+    NotificationRegistrar registrar_;

[brettw, 2011/01/03 19:48:30]

Can you put a blank line above this?

+    // The time when we started benchmarking.
+    base::TimeTicks start_;
+    // The last time we got a paint notification.
+    base::TimeTicks last_paint_;
+    // Scoping so we can be sure our timeouts don't outlive us.
+    base::OneShotTimer<PaintTimer> timer_;
+
+    DISALLOW_COPY_AND_ASSIGN(PaintTimer);
+  };
 
   virtual void Observe(NotificationType type,
                        const NotificationSource& source,
                        const NotificationDetails& details);
 
   // Reset the CSS caches.
   void InitializeCSSCaches();
 
   // Updates the user prefs version and calls |MigrateUserPrefs| if needed.
   // Returns true if the version was updated.
   static bool UpdateUserPrefsVersion(PrefService* prefs);
 
   NotificationRegistrar registrar_;
 
+  scoped_ptr<PaintTimer> paint_timer_;
+
   // The preference version. This used for migrating prefs of the NTP.
   static const int current_pref_version_ = 3;
 
   DISALLOW_COPY_AND_ASSIGN(NewTabUI);
 };
 
 #endif  // CHROME_BROWSER_DOM_UI_NEW_TAB_UI_H_