Port History::QueryMostVisitedURLs to use CancelableTaskTracker

chrome/browser/history/top_sites_impl.h

 // Copyright (c) 2013 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_HISTORY_TOP_SITES_IMPL_H_
 #define CHROME_BROWSER_HISTORY_TOP_SITES_IMPL_H_
 
 #include <list>
 #include <set>
 #include <string>
@@ skipping 198 matching lines @@
 
   // Stops and starts timer with a delay of |delta|.
   void RestartQueryForTopSitesTimer(base::TimeDelta delta);
 
   // Callback from TopSites with the top sites/thumbnails. Should be called
   // from the UI thread.
   void OnGotMostVisitedThumbnails(
       const scoped_refptr<MostVisitedThumbnails>& thumbnails);
 
   // Called when history service returns a list of top URLs.
-  void OnTopSitesAvailableFromHistory(CancelableRequestProvider::Handle handle,
-                                      MostVisitedURLList data);
+  void OnTopSitesAvailableFromHistory(const MostVisitedURLList* data);
 
   scoped_refptr<TopSitesBackend> backend_;
 
   // The top sites data.
   scoped_ptr<TopSitesCache> cache_;
 
   // Copy of the top sites data that may be accessed on any thread (assuming
   // you hold |lock_|). The data in |thread_safe_cache_| has blacklisted and
   // pinned urls applied (|cache_| does not).
   scoped_ptr<TopSitesCache> thread_safe_cache_;
@@ skipping 36 matching lines @@
 
   // Are we loaded?
   bool loaded_;
 
   DISALLOW_COPY_AND_ASSIGN(TopSitesImpl);
 };
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_TOP_SITES_IMPL_H_