Start PopularSites fetch from separate function.

components/ntp_tiles/most_visited_sites.h

 // Copyright 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 COMPONENTS_NTP_TILES_MOST_VISITED_SITES_H_
 #define COMPONENTS_NTP_TILES_MOST_VISITED_SITES_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 133 matching lines @@
 
     Suggestion(Suggestion&&);
     Suggestion& operator=(Suggestion&&);
 
    private:
     DISALLOW_COPY_AND_ASSIGN(Suggestion);
   };
 
   MostVisitedSites(scoped_refptr<base::SequencedWorkerPool> blocking_pool,
                    PrefService* prefs,
-                   const TemplateURLService* template_url_service,
-                   variations::VariationsService* variations_service,
-                   net::URLRequestContextGetter* download_context,
-                   const base::FilePath& popular_sites_directory,
                    scoped_refptr<history::TopSites> top_sites,
                    suggestions::SuggestionsService* suggestions,
+                   PopularSites* popular_sites,
                    MostVisitedSitesSupervisor* supervisor);
 
   ~MostVisitedSites() override;
 
 #if defined(OS_ANDROID)
   static bool Register(JNIEnv* env);
 #endif
 
   // Does not take ownership of |observer|, which must outlive this object and
   // must not be null.
@@ skipping 59 matching lines @@
 
   // Records UMA histogram metrics related to the number of impressions.
   void RecordImpressionUMAMetrics();
 
   // history::TopSitesObserver implementation.
   void TopSitesLoaded(history::TopSites* top_sites) override;
   void TopSitesChanged(history::TopSites* top_sites,
                        ChangeReason change_reason) override;
 
   PrefService* prefs_;
-  const TemplateURLService* template_url_service_;
-  variations::VariationsService* variations_service_;
-  net::URLRequestContextGetter* download_context_;
-  base::FilePath popular_sites_directory_;
   scoped_refptr<history::TopSites> top_sites_;
   suggestions::SuggestionsService* suggestions_service_;
+  PopularSites* const popular_sites_;
   MostVisitedSitesSupervisor* supervisor_;
 
   Observer* observer_;
 
   // The maximum number of most visited sites to return.
   int num_sites_;
 
   // Whether we have received an initial set of most visited sites (from either
   // TopSites or the SuggestionsService).
   bool received_most_visited_sites_;
 
   // Whether we have received the set of popular sites. Immediately set to true
   // if popular sites are disabled.
   bool received_popular_sites_;
 
   // Whether we have recorded one-shot UMA metrics such as impressions. They are
   // recorded once both the previous flags are true.
   bool recorded_uma_;
 
   std::unique_ptr<
       suggestions::SuggestionsService::ResponseCallbackList::Subscription>
       suggestions_subscription_;
 
   ScopedObserver<history::TopSites, history::TopSitesObserver> scoped_observer_;
 
   MostVisitedSource mv_source_;
 
-  std::unique_ptr<PopularSites> popular_sites_;
-
   SuggestionsVector current_suggestions_;
 
   base::ThreadChecker thread_checker_;
-  scoped_refptr<base::SequencedWorkerPool> blocking_pool_;
   scoped_refptr<base::TaskRunner> blocking_runner_;
 
   // For callbacks may be run after destruction.
   base::WeakPtrFactory<MostVisitedSites> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MostVisitedSites);
 };
 
 }  // namespace ntp_tiles
 
 #endif  // COMPONENTS_NTP_TILES_MOST_VISITED_SITES_H_