[NTP::PhysicalWeb] Implement suggestion dismissal.

components/ntp_snippets/offline_pages/recent_tab_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 COMPONENTS_NTP_SNIPPETS_OFFLINE_PAGES_RECENT_TAB_SUGGESTIONS_PROVIDER_H_
 #define COMPONENTS_NTP_SNIPPETS_OFFLINE_PAGES_RECENT_TAB_SUGGESTIONS_PROVIDER_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 80 matching lines @@
 
   // Removes duplicates for the same URL leaving only the most recently created
   // items, returns at most |GetMaxSuggestionsCount()| ContentSuggestions
   // corresponding to the remaining items, sorted by creation time (newer
   // first).
   std::vector<ContentSuggestion> GetMostRecentlyCreatedWithoutDuplicates(
       std::vector<const offline_pages::OfflinePageItem*> offline_page_items)
       const;
 
   // Fires the |OnSuggestionInvalidated| event for the suggestion corresponding
-  // to the given |offline_id| and clears it from the dismissed IDs list, if
+  // to the given |offline_id| and deletes it from the dismissed IDs list, if
   // necessary.
   void InvalidateSuggestion(int64_t offline_id);
 
   // Reads dismissed IDs from Prefs.
   std::set<std::string> ReadDismissedIDsFromPrefs() const;
 
   // Writes |dismissed_ids| into Prefs.
   void StoreDismissedIDsToPrefs(const std::set<std::string>& dismissed_ids);
 
   CategoryStatus category_status_;
   const Category provided_category_;
   offline_pages::OfflinePageModel* offline_page_model_;
 
   PrefService* pref_service_;
 
   base::WeakPtrFactory<RecentTabSuggestionsProvider> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RecentTabSuggestionsProvider);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_OFFLINE_PAGES_RECENT_TAB_SUGGESTIONS_PROVIDER_H_