Move OnURLsDeleted from NTPSnippetsService to ContentSuggestionsService

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 <string>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/observer_list.h"
 #include "base/optional.h"
+#include "base/scoped_observer.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/category_factory.h"
 #include "components/ntp_snippets/category_status.h"
 #include "components/ntp_snippets/content_suggestions_provider.h"
 
 namespace gfx {
 class Image;
 }
 
 namespace ntp_snippets {
 
 class NTPSnippetsService;
 
 // 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 ContentSuggestionsProvider::Observer,
+                                  public history::HistoryServiceObserver {
  public:
   using ImageFetchedCallback =
       base::Callback<void(const std::string& suggestion_id, const gfx::Image&)>;
   using DismissedSuggestionsCallback = base::Callback<void(
       std::vector<ContentSuggestion> dismissed_suggestions)>;
 
   class Observer {
    public:
     // Fired every time the service receives a new set of data for the given
     // |category|, replacing any previously available data (though in most cases
@@ skipping 26 matching lines @@
 
    protected:
     virtual ~Observer() {}
   };
 
   enum State {
     ENABLED,
     DISABLED,
   };
 
-  ContentSuggestionsService(State state);
+  ContentSuggestionsService(State state,
+                            history::HistoryService* history_service);
   ~ContentSuggestionsService() override;
 
   // Inherited from KeyedService.
   void Shutdown() override;
 
   State state() { return state_; }
 
   // Gets all categories for which a provider is registered. The categories
   // may or may not be available, see |GetCategoryStatus()|.
   const std::vector<Category>& GetCategories() const { return categories_; }
@@ skipping 84 matching lines @@
   void OnNewSuggestions(ContentSuggestionsProvider* provider,
                         Category category,
                         std::vector<ContentSuggestion> suggestions) override;
   void OnCategoryStatusChanged(ContentSuggestionsProvider* provider,
                                Category category,
                                CategoryStatus new_status) override;
   void OnSuggestionInvalidated(ContentSuggestionsProvider* provider,
                                Category category,
                                const std::string& suggestion_id) override;
 
+  // history::HistoryServiceObserver implementation.
+  void OnURLsDeleted(history::HistoryService* history_service,
+                     bool all_history,
+                     bool expired,
+                     const history::URLRows& deleted_rows,
+                     const std::set<GURL>& favicon_urls) override;
+  void HistoryServiceBeingDeleted(
+      history::HistoryService* history_service) override;
+
   // Registers the given |provider| for the given |category|, unless it is
   // already registered. Returns true if the category was newly registered or
   // false if it was present before.
   bool RegisterCategoryIfRequired(ContentSuggestionsProvider* provider,
                                   Category category);
 
   // Removes a suggestion from the local stores |id_category_map_| and
   // |suggestions_by_category_|, if it exists. Returns true if a suggestion was
   // removed.
   bool RemoveSuggestionByID(Category category,
@@ skipping 30 matching lines @@
   // contain an empty vector if the category is available but empty (or still
   // loading).
   std::map<Category, std::vector<ContentSuggestion>, Category::CompareByID>
       suggestions_by_category_;
 
   // Map used to determine the category of a suggestion (of which only the ID
   // is available). This also determines the provider that delivered the
   // suggestion.
   std::map<std::string, Category> id_category_map_;
 
+  // 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_;
 
   // Keep a direct reference to this special provider to redirect scheduling,
   // background fetching and debugging calls to it. If the NTPSnippetsService is
   // loaded, it is also present in |providers_|, otherwise this is a nullptr.
   NTPSnippetsService* ntp_snippets_service_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentSuggestionsService);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_CONTENT_SUGGESTIONS_SERVICE_H_