Associate a scan mode with Physical Web listeners

components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.cc

 // 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.
 
 #include "components/ntp_snippets/physical_web_pages/physical_web_page_suggestions_provider.h"
 
 #include <algorithm>
 #include <memory>
 #include <set>
 #include <string>
@@ skipping 80 matching lines @@
     ContentSuggestionsProvider::Observer* observer,
     physical_web::PhysicalWebDataSource* physical_web_data_source,
     PrefService* pref_service)
     : ContentSuggestionsProvider(observer),
       category_status_(CategoryStatus::AVAILABLE),
       provided_category_(
           Category::FromKnownCategory(KnownCategories::PHYSICAL_WEB_PAGES)),
       physical_web_data_source_(physical_web_data_source),
       pref_service_(pref_service) {
   observer->OnCategoryStatusChanged(this, provided_category_, category_status_);
-  physical_web_data_source_->RegisterListener(this);
+  physical_web_data_source_->RegisterListener(this,
+      physical_web::BACKGROUND_INTERMITTENT);
   // TODO(vitaliii): Rewrite initial fetch once crbug.com/667754 is resolved.
   FetchPhysicalWebPages();
 }
 
 PhysicalWebPageSuggestionsProvider::~PhysicalWebPageSuggestionsProvider() {
   physical_web_data_source_->UnregisterListener(this);
 }
 
 CategoryStatus PhysicalWebPageSuggestionsProvider::GetCategoryStatus(
     Category category) {
@@ skipping 246 matching lines @@
 }
 
 void PhysicalWebPageSuggestionsProvider::StoreDismissedIDsToPrefs(
     const std::set<std::string>& dismissed_ids) {
   prefs::StoreDismissedIDsToPrefs(pref_service_,
                                   prefs::kDismissedPhysicalWebPageSuggestions,
                                   dismissed_ids);
 }
 
 }  // namespace ntp_snippets