[Popular Sites] Move PopularSitesImpl to dedicated file

components/ntp_tiles/popular_sites.h

Index: components/ntp_tiles/popular_sites.h
diff --git a/components/ntp_tiles/popular_sites.h b/components/ntp_tiles/popular_sites.h
index 104ae63cd313061cd37e6e7829808724c1aa4773..76329526f010a47a5aea2e73e6ca901ea377baf6 100644
--- a/components/ntp_tiles/popular_sites.h
+++ b/components/ntp_tiles/popular_sites.h
@@ -5,44 +5,16 @@
 #ifndef COMPONENTS_NTP_TILES_POPULAR_SITES_H_
 #define COMPONENTS_NTP_TILES_POPULAR_SITES_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 "net/url_request/url_fetcher_delegate.h"
 #include "url/gurl.h"
 
-namespace base {
-class Value;
-}
-
-namespace net {
-class URLRequestContextGetter;
-}
-
-namespace user_prefs {
-class PrefRegistrySyncable;
-}
-
-namespace variations {
-class VariationsService;
-}
-
-class PrefService;
-class TemplateURLService;
-
 namespace ntp_tiles {
 
-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)>;
-
 // Interface to provide a list of suggested popular sites, for display on the
 // NTP when there are not enough personalized tiles.
 class PopularSites {
@@ -92,73 +64,6 @@ class PopularSites {
   virtual std::string GetVersionToFetch() = 0;
 };
 
-// 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.
-  void StartFetch(bool force_download,
-                  const FinishedCallback& callback) override;
-  const SitesVector& sites() const override;
-  GURL GetLastURLFetched() const override;
-  const base::FilePath& local_path() const override;
-  GURL GetURLToFetch() override;
-  std::string GetCountryToFetch() override;
-  std::string GetVersionToFetch() override;
-
-  // Register preferences used by this class.
-  static void RegisterProfilePrefs(
-      user_prefs::PrefRegistrySyncable* user_prefs);
-
- private:
-  void OnReadFileDone(std::unique_ptr<std::string> data, bool success);
-
-  // Fetch the popular sites at the given URL, overwriting any file that already
-  // exists.
-  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 OnFileWriteDone(std::unique_ptr<base::Value> json, bool success);
-  void ParseSiteList(std::unique_ptr<base::Value> json);
-  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_;
-  base::FilePath const local_path_;
-  ParseJSONCallback parse_json_;
-
-  // Set by StartFetch() 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_H_