[Content suggestions] Implement fetching publishers' favicons

components/ntp_snippets/content_suggestions_service.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_SNIPPETS_CONTENT_SUGGESTIONS_SERVICE_H_
 #define COMPONENTS_NTP_SNIPPETS_CONTENT_SUGGESTIONS_SERVICE_H_
 
 #include <map>
 #include <memory>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/observer_list.h"
 #include "base/optional.h"
 #include "base/scoped_observer.h"
+#include "base/task/cancelable_task_tracker.h"
 #include "base/time/time.h"
 #include "components/history/core/browser/history_service.h"
 #include "components/history/core/browser/history_service_observer.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/ntp_snippets/callbacks.h"
 #include "components/ntp_snippets/category.h"
 #include "components/ntp_snippets/category_rankers/category_ranker.h"
 #include "components/ntp_snippets/category_status.h"
 #include "components/ntp_snippets/content_suggestions_provider.h"
 #include "components/ntp_snippets/remote/remote_suggestions_scheduler.h"
 #include "components/ntp_snippets/user_classifier.h"
 #include "components/signin/core/browser/signin_manager.h"
 
 class PrefService;
 class PrefRegistrySimple;
 
+namespace favicon {
+class LargeIconService;
+}  // namespace favicon
+
+namespace favicon_base {
+struct LargeIconImageResult;
+}  // namespace favicon_base
+
 namespace ntp_snippets {
 
 class RemoteSuggestionsProvider;
 
 // Retrieves suggestions from a number of ContentSuggestionsProviders and serves
 // them grouped into categories. There can be at most one provider per category.
 class ContentSuggestionsService : public KeyedService,
                                   public ContentSuggestionsProvider::Observer,
                                   public SigninManagerBase::Observer,
                                   public history::HistoryServiceObserver {
@@ skipping 39 matching lines @@
 
   enum State {
     ENABLED,
     DISABLED,
   };
 
   ContentSuggestionsService(
       State state,
       SigninManagerBase* signin_manager,         // Can be nullptr in unittests.
       history::HistoryService* history_service,  // Can be nullptr in unittests.
+      favicon::LargeIconService*
+          large_icon_service,  // Can be nullptr in unittests.

[Bernhard Bauer, 2017/03/31 16:45:16]

Nit: I would move the comment to the previous line and keep the code on a single
line.

[jkrcal, 2017/04/03 12:37:36]

Done.

       PrefService* pref_service,
       std::unique_ptr<CategoryRanker> category_ranker,
       std::unique_ptr<UserClassifier> user_classifier,
       std::unique_ptr<RemoteSuggestionsScheduler>
           remote_suggestions_scheduler  // Can be nullptr in unittests.
       );
   ~ContentSuggestionsService() override;
 
   // Inherited from KeyedService.
   void Shutdown() override;
@@ skipping 194 matching lines @@
   void NotifyCategoryStatusChanged(Category category);
 
   void OnSignInStateChanged();
 
   // Re-enables a dismissed category, making querying its provider possible.
   void RestoreDismissedCategory(Category category);
 
   void RestoreDismissedCategoriesFromPrefs();
   void StoreDismissedCategoriesToPrefs();
 
+  // Callbacks for fetching favicons.
+  void OnGetFaviconFromCacheFinished(
+      const GURL& publisher_url,
+      int minimum_size_in_pixel,
+      int desired_size_in_pixel,
+      const ImageFetchedCallback& callback,
+      bool continue_to_google_server,
+      const favicon_base::LargeIconImageResult& result);
+  void OnGetFaviconFromGoogleServerFinished(
+      const GURL& publisher_url,
+      int minimum_size_in_pixel,
+      int desired_size_in_pixel,
+      const ImageFetchedCallback& callback,
+      bool success);
+
   // Whether the content suggestions feature is enabled.
   State state_;
 
   // All registered providers, owned by the service.
   std::vector<std::unique_ptr<ContentSuggestionsProvider>> providers_;
 
   // All registered categories and their providers. A provider may be contained
   // multiple times, if it provides multiple categories. The keys of this map
   // are exactly the entries of |categories_| and the values are a subset of
   // |providers_|.
@@ skipping 25 matching lines @@
 
   // Observer for the HistoryService. All providers are notified when history is
   // deleted.
   ScopedObserver<history::HistoryService, history::HistoryServiceObserver>
       history_service_observer_;
 
   base::ObserverList<Observer> observers_;
 
   const std::vector<ContentSuggestion> no_suggestions_;
 
+  base::CancelableTaskTracker favicons_task_tracker_;
+
   // Keep a direct reference to this special provider to redirect debugging
   // calls to it. If the RemoteSuggestionsProvider is loaded, it is also present
   // in |providers_|, otherwise this is a nullptr.
   RemoteSuggestionsProvider* remote_suggestions_provider_;
 
+  favicon::LargeIconService* large_icon_service_;
+
   PrefService* pref_service_;
 
   // Interface for informing about external events that have influence on
   // scheduling remote fetches.
   std::unique_ptr<RemoteSuggestionsScheduler> remote_suggestions_scheduler_;
 
   // Classifies the user on the basis of long-term user interactions.
   std::unique_ptr<UserClassifier> user_classifier_;
 
   // Provides order for categories.
   std::unique_ptr<CategoryRanker> category_ranker_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentSuggestionsService);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_CONTENT_SUGGESTIONS_SERVICE_H_