[NTP::Downloads] Do not show old downloads.

chrome/browser/ntp_snippets/download_suggestions_provider.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 CHROME_BROWSER_NTP_SNIPPETS_DOWNLOAD_SUGGESTIONS_PROVIDER_H_
 #define CHROME_BROWSER_NTP_SNIPPETS_DOWNLOAD_SUGGESTIONS_PROVIDER_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 10 matching lines @@
 #include "components/offline_pages/core/offline_page_model.h"
 #include "content/public/browser/download_manager.h"
 
 class PrefRegistrySimple;
 class PrefService;
 
 namespace offline_pages {
 struct OfflinePageItem;
 }
 
+namespace base {
+class Clock;
+}
+
 // Provides download content suggestions from the offline pages model and the
 // download manager (obtaining the data through DownloadManager and each
 // DownloadItem). Offline page related downloads are referred to as offline page
 // downloads, while the remaining downloads (e.g. images, music, books) are
 // called asset downloads. In case either of the data sources is |nullptr|, it
 // is ignored.
 class DownloadSuggestionsProvider
     : public ntp_snippets::ContentSuggestionsProvider,
       public offline_pages::OfflinePageModel::Observer,
       public content::DownloadManager::Observer,
       public content::DownloadItem::Observer,
       public DownloadHistory::Observer {
  public:
   DownloadSuggestionsProvider(
       ContentSuggestionsProvider::Observer* observer,
       offline_pages::OfflinePageModel* offline_page_model,
       content::DownloadManager* download_manager,
       DownloadHistory* download_history,
-      PrefService* pref_service);
+      PrefService* pref_service,
+      std::unique_ptr<base::Clock> clock);
   ~DownloadSuggestionsProvider() override;
 
   // ContentSuggestionsProvider implementation.
   ntp_snippets::CategoryStatus GetCategoryStatus(
       ntp_snippets::Category category) override;
   ntp_snippets::CategoryInfo GetCategoryInfo(
       ntp_snippets::Category category) override;
   void DismissSuggestion(
       const ntp_snippets::ContentSuggestion::ID& suggestion_id) override;
   void FetchSuggestionImage(
@@ skipping 69 matching lines @@
 
   // Converts an OfflinePageItem to a ContentSuggestion for the
   // |provided_category_|.
   ntp_snippets::ContentSuggestion ConvertOfflinePage(
       const offline_pages::OfflinePageItem& offline_page) const;
 
   // Converts DownloadItem to a ContentSuggestion for the |provided_category_|.
   ntp_snippets::ContentSuggestion ConvertDownloadItem(
       const content::DownloadItem& download_item) const;
 
+  // Returns true if a download published time is too old to be shown.
+  bool IsDownloadOld(const base::Time& published_time);

[tschumann, 2017/02/02 14:30:34]

'old' is a bit short on semantics.
Should we call it 'expired', 'stale', or 'outdated'?

[vitaliii, 2017/02/07 10:26:05]

Done. "Outdated"

+
   // Adds |item| to the internal asset download cache if all of the following
   // holds:
   // - the download is completed;
   // - its suggestion has not been dismissed;
   // - there are less than |kMaxSuggestionsCount| items cached or the oldest
   //     cached item is older than the current item (the oldest item is removed
   //     then);
   // - the item is not present in the cache yet.
   // Returns |true| if the item has been added.
   bool CacheAssetDownloadIfNeeded(const content::DownloadItem* item);
@@ skipping 49 matching lines @@
   void StoreDismissedIDsToPrefs(bool for_offline_page_downloads,
                                 const std::set<std::string>& dismissed_ids);
 
   void UnregisterDownloadItemObservers();
 
   ntp_snippets::CategoryStatus category_status_;
   const ntp_snippets::Category provided_category_;
   offline_pages::OfflinePageModel* offline_page_model_;
   content::DownloadManager* download_manager_;
   DownloadHistory* download_history_;
-
   PrefService* pref_service_;
+  std::unique_ptr<base::Clock> clock_;
 
   // Cached offline page downloads. If there are not enough asset downloads, all
   // of these could be shown (they are the most recently visited, not dismissed
   // and not invalidated). Order is undefined. If the model has less than
   // |kMaxSuggestionsCount| offline pages, then all of them which satisfy the
   // criteria above are cached, otherwise only |kMaxSuggestionsCount|.
   std::vector<offline_pages::OfflinePageItem> cached_offline_page_downloads_;
   // Cached asset downloads. If there are not enough offline page downloads, all
   // of these could be shown (they are the most recently downloaded, not
   // dismissed and not invalidated). Order is undefined. If the model has less
   // than |kMaxSuggestionsCount| asset downloads, then all of them which satisfy
   // the criteria above are cached, otherwise only |kMaxSuggestionsCount|.
   std::vector<const content::DownloadItem*> cached_asset_downloads_;
 
   bool is_asset_downloads_initialization_complete_;
 
   base::WeakPtrFactory<DownloadSuggestionsProvider> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadSuggestionsProvider);
 };
 
 #endif  // CHROME_BROWSER_NTP_SNIPPETS_DOWNLOAD_SUGGESTIONS_PROVIDER_H_