Remove deleted offline page suggestions from opened NTPs

chrome/browser/ui/webui/snippets_internals_message_handler.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_UI_WEBUI_SNIPPETS_INTERNALS_MESSAGE_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_SNIPPETS_INTERNALS_MESSAGE_HANDLER_H_
 
 #include <string>
 
 #include "base/macros.h"
@@ skipping 18 matching lines @@
 
  private:
   // content::WebUIMessageHandler:
   void RegisterMessages() override;
 
   // ntp_snippets::ContentSuggestionsService::Observer:
   void OnNewSuggestions(ntp_snippets::Category category) override;
   void OnCategoryStatusChanged(
       ntp_snippets::Category category,
       ntp_snippets::CategoryStatus new_status) override;
+  void OnSuggestionInvalidated(ntp_snippets::Category category,
+                               const std::string& suggestion_id) override;
   void ContentSuggestionsServiceShutdown() override;
 
   void HandleRefreshContent(const base::ListValue* args);
   void HandleDownload(const base::ListValue* args);
   void HandleClearCachedSuggestions(const base::ListValue* args);
   void HandleClearDismissedSuggestions(const base::ListValue* args);
 
   void SendAllContent();
   void SendHosts();
   void SendContentSuggestions();
   void SendBoolean(const std::string& name, bool value);
   void SendString(const std::string& name, const std::string& value);
 
   ScopedObserver<ntp_snippets::ContentSuggestionsService,
                  ntp_snippets::ContentSuggestionsService::Observer>
       content_suggestions_service_observer_;
 
   // Tracks whether we can already send messages to the page.
   bool dom_loaded_;
 
   ntp_snippets::NTPSnippetsService* ntp_snippets_service_;
   ntp_snippets::ContentSuggestionsService* content_suggestions_service_;
 
   DISALLOW_COPY_AND_ASSIGN(SnippetsInternalsMessageHandler);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_SNIPPETS_INTERNALS_MESSAGE_HANDLER_H_