Remove legacy popular sites cache cleaning

components/ntp_tiles/popular_sites_impl.h

 // Copyright 2016 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_POPULAR_SITES_IMPL_H_
 #define COMPONENTS_NTP_TILES_POPULAR_SITES_IMPL_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
-#include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string16.h"
 #include "components/ntp_tiles/popular_sites.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "url/gurl.h"
 
 namespace base {
-class TaskRunner;
-class SequencedWorkerPool;
 class Value;
 }
 
 namespace net {
 class URLRequestContextGetter;
 }
 
 namespace user_prefs {
 class PrefRegistrySyncable;
 }
@@ skipping 10 matching lines @@
 using ParseJSONCallback = base::Callback<void(
     const std::string& unsafe_json,
     const base::Callback<void(std::unique_ptr<base::Value>)>& success_callback,
     const base::Callback<void(const std::string&)>& error_callback)>;
 
 // Actual (non-test) implementation of the PopularSites interface. Caches the
 // downloaded file on disk to avoid re-downloading on every startup.
 class PopularSitesImpl : public PopularSites, public net::URLFetcherDelegate {
  public:
   PopularSitesImpl(
-      const scoped_refptr<base::SequencedWorkerPool>& blocking_pool,
       PrefService* prefs,
       const TemplateURLService* template_url_service,
       variations::VariationsService* variations_service,
       net::URLRequestContextGetter* download_context,
-      const base::FilePath& directory,
       ParseJSONCallback parse_json);
 
   ~PopularSitesImpl() override;
 
   // PopularSites implementation.
   bool MaybeStartFetch(bool force_download,
                        const FinishedCallback& callback) override;
   const SitesVector& sites() const override;
   GURL GetLastURLFetched() const override;
   GURL GetURLToFetch() override;
@@ skipping 12 matching lines @@
   void FetchPopularSites();
 
   // net::URLFetcherDelegate implementation.
   void OnURLFetchComplete(const net::URLFetcher* source) override;
 
   void OnJsonParsed(std::unique_ptr<base::Value> json);
   void OnJsonParseFailed(const std::string& error_message);
   void OnDownloadFailed();
 
   // Parameters set from constructor.
-  scoped_refptr<base::TaskRunner> const blocking_runner_;
   PrefService* const prefs_;
   const TemplateURLService* const template_url_service_;
   variations::VariationsService* const variations_;
   net::URLRequestContextGetter* const download_context_;
   ParseJSONCallback parse_json_;
 
   // Set by MaybeStartFetch() and called after fetch completes.
   FinishedCallback callback_;
 
   std::unique_ptr<net::URLFetcher> fetcher_;
   bool is_fallback_;
   SitesVector sites_;
   GURL pending_url_;
 
   base::WeakPtrFactory<PopularSitesImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PopularSitesImpl);
 };
 
 }  // namespace ntp_tiles
 
 #endif  // COMPONENTS_NTP_TILES_POPULAR_SITES_IMPL_H_