Filter out redundant jumplist updates.

chrome/browser/jumplist_win.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_JUMPLIST_WIN_H_
 #define CHROME_BROWSER_JUMPLIST_WIN_H_
 
 #include <list>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/files/file_path.h"
 #include "base/memory/weak_ptr.h"
 #include "base/synchronization/lock.h"
 #include "base/task/cancelable_task_tracker.h"
+#include "base/timer/timer.h"
 #include "chrome/browser/jumplist_updater_win.h"
 #include "chrome/browser/prefs/incognito_mode_prefs.h"
 #include "chrome/browser/sessions/tab_restore_service.h"
 #include "chrome/browser/sessions/tab_restore_service_observer.h"
 #include "components/history/core/browser/history_service.h"
 #include "components/history/core/browser/history_types.h"
 #include "components/history/core/browser/top_sites_observer.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
@@ skipping 91 matching lines @@
   // the list.
   void OnMostVisitedURLsAvailable(
       const history::MostVisitedURLList& data);
 
   // Callback for changes to the incognito mode availability pref.
   void OnIncognitoAvailabilityChanged();
 
   // Helper for RunUpdate() that determines its parameters.
   void PostRunUpdate();
 
+  // Called on a timer to invoke RunUpdateOnFileThread() after requests storms
+  // have subsided.
+  void DeferredRunUpdate();
+
   // Runnable method that updates the jumplist, once all the data
   // has been fetched.
   void RunUpdateOnFileThread(
       IncognitoModePrefs::Availability incognito_availability);
 
   // Helper method for RunUpdate to create icon files for the asynchrounously
   // loaded icons.
   void CreateIconFiles(const ShellLinkItemList& item_list);
 
   // history::TopSitesObserver implementation.
@@ skipping 17 matching lines @@
   base::FilePath icon_dir_;
 
   // Items in the "Most Visited" category of the application JumpList,
   // protected by the list_lock_.
   ShellLinkItemList most_visited_pages_;
 
   // Items in the "Recently Closed" category of the application JumpList,
   // protected by the list_lock_.
   ShellLinkItemList recently_closed_pages_;
 
+  // Timer for requesting delayed updates of the jumplist.
+  base::OneShotTimer<JumpList> timer_;
+
   // A list of URLs we need to retrieve their favicons,
   // protected by the list_lock_.
   typedef std::pair<std::string, scoped_refptr<ShellLinkItem> > URLPair;
   std::list<URLPair> icon_urls_;
 
   // Id of last favicon task. It's used to cancel current task if a new one
   // comes in before it finishes.
   base::CancelableTaskTracker::TaskId task_id_;
 
   // Lock for most_visited_pages_, recently_closed_pages_, icon_urls_
   // as they may be used by up to 3 threads.
   base::Lock list_lock_;
 
   // For callbacks may be run after destruction.
   base::WeakPtrFactory<JumpList> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(JumpList);
 };
 
 #endif  // CHROME_BROWSER_JUMPLIST_WIN_H_