[NTP::Downloads] Fetch assets once the manager is loaded.

chrome/browser/ntp_snippets/download_suggestions_provider.h

Index: chrome/browser/ntp_snippets/download_suggestions_provider.h
diff --git a/chrome/browser/ntp_snippets/download_suggestions_provider.h b/chrome/browser/ntp_snippets/download_suggestions_provider.h
index 5ee5baf25853edef5678104e8f3436945cf55fd4..a6f2fb39baface16a0468e04516fefc38febc339 100644
--- a/chrome/browser/ntp_snippets/download_suggestions_provider.h
+++ b/chrome/browser/ntp_snippets/download_suggestions_provider.h
@@ -12,6 +12,7 @@
 #include "base/callback_forward.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/weak_ptr.h"
+#include "chrome/browser/download/download_history.h"
 #include "components/ntp_snippets/callbacks.h"
 #include "components/ntp_snippets/category.h"
 #include "components/ntp_snippets/category_status.h"
@@ -37,12 +38,14 @@ class DownloadSuggestionsProvider
     : public ntp_snippets::ContentSuggestionsProvider,
       public offline_pages::OfflinePageModel::Observer,
       public content::DownloadManager::Observer,
-      public content::DownloadItem::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,
       bool download_manager_ui_enabled);
   ~DownloadSuggestionsProvider() override;
@@ -73,8 +76,6 @@ class DownloadSuggestionsProvider
 
   static void RegisterProfilePrefs(PrefRegistrySimple* registry);
 
-  static int GetMaxDismissedCountForTesting();
-
  private:
   friend class DownloadSuggestionsProviderTest;
 
@@ -101,6 +102,10 @@ class DownloadSuggestionsProvider
   void OnDownloadRemoved(content::DownloadItem* item) override;
   void OnDownloadDestroyed(content::DownloadItem* item) override;
 
+  // DownloadHistory::Observer implementation.
+  void OnHistoryQueryComplete() override;
+  void OnDownloadHistoryDestroyed() override;
+
   // Updates the |category_status_| of the |provided_category_| and notifies the
   // |observer_|, if necessary.
   void NotifyStatusChanged(ntp_snippets::CategoryStatus new_status);
@@ -171,11 +176,11 @@ class DownloadSuggestionsProvider
   void InvalidateSuggestion(const std::string& id_within_category);
 
   // Reads dismissed IDs related to asset downloads from prefs.
-  std::vector<std::string> ReadAssetDismissedIDsFromPrefs() const;
+  std::set<std::string> ReadAssetDismissedIDsFromPrefs() const;
 
   // Writes |dismissed_ids| into prefs for asset downloads.
   void StoreAssetDismissedIDsToPrefs(
-      const std::vector<std::string>& dismissed_ids);
+      const std::set<std::string>& dismissed_ids);
 
   // Reads dismissed IDs related to offline page downloads from prefs.
   std::set<std::string> ReadOfflinePageDismissedIDsFromPrefs() const;
@@ -184,15 +189,15 @@ class DownloadSuggestionsProvider
   void StoreOfflinePageDismissedIDsToPrefs(
       const std::set<std::string>& dismissed_ids);
 
-  // Adds a suggestion ID to the dismissed list in prefs, if it is not there.
-  // Works for both Offline Page and Asset downloads.
-  void AddToDismissedStorageIfNeeded(
-      const ntp_snippets::ContentSuggestion::ID& suggestion_id);
+  // Reads from prefs dismissed IDs related to either offline page or asset
+  // downloads (given by |for_offline_page_downloads|).
+  std::set<std::string> ReadDismissedIDsFromPrefs(
+      bool for_offline_page_downloads) const;
 
-  // Removes a suggestion ID from the dismissed list in prefs, if it is there.
-  // Works for both Offline Page and Asset downloads.
-  void RemoveFromDismissedStorageIfNeeded(
-      const ntp_snippets::ContentSuggestion::ID& suggestion_id);
+  // Writes |dismissed_ids| into prefs for either offline page or asset
+  // downloads (given by |for_offline_page_downloads|).
+  void StoreDismissedIDsToPrefs(bool for_offline_page_downloads,
+                                const std::set<std::string>& dismissed_ids);
 
   void UnregisterDownloadItemObservers();
 
@@ -200,6 +205,7 @@ class DownloadSuggestionsProvider
   const ntp_snippets::Category provided_category_;
   offline_pages::OfflinePageModel* offline_page_model_;
   content::DownloadManager* download_manager_;
+  DownloadHistory* download_history_;
 
   PrefService* pref_service_;
 
@@ -220,6 +226,8 @@ class DownloadSuggestionsProvider
   // for the Downloads section can redirect there.
   const bool download_manager_ui_enabled_;
 
+  bool is_asset_downloads_initialization_complete_;
+
   base::WeakPtrFactory<DownloadSuggestionsProvider> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadSuggestionsProvider);