[NTP Snippets] Add a pref to disable the NTPSnippetsService

components/ntp_snippets/ntp_snippets_service.cc

 // Copyright 2015 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/ntp_snippets_service.h"
 
 #include <algorithm>
 #include <iterator>
 #include <utility>
 
@@ skipping 219 matching lines @@
                                      base::Unretained(this)));
 }
 
 NTPSnippetsService::~NTPSnippetsService() {
   DCHECK(state_ == State::SHUT_DOWN);
 }
 
 // static
 void NTPSnippetsService::RegisterProfilePrefs(PrefRegistrySimple* registry) {
   registry->RegisterListPref(prefs::kSnippetHosts);
+
+  NTPSnippetsStatusService::RegisterProfilePrefs(registry);
 }
 
 // Inherited from KeyedService.
 void NTPSnippetsService::Shutdown() {
   EnterState(State::SHUT_DOWN, ContentSuggestionsCategoryStatus::NOT_PROVIDED);
 }
 
 void NTPSnippetsService::FetchSnippets() {
   if (ready())
     FetchSnippetsFromHosts(GetSuggestionsHosts());
@@ skipping 436 matching lines @@
   snippets_fetcher_->SetCallback(
       base::Bind(&NTPSnippetsService::OnFetchFinished, base::Unretained(this)));
 
   // |image_fetcher_| can be null in tests.
   if (image_fetcher_)
     image_fetcher_->SetImageFetcherDelegate(this);
 
   // Note: Initializing the status service will run the callback right away with
   // the current state.
   snippets_status_service_->Init(base::Bind(
-      &NTPSnippetsService::UpdateStateForStatus, base::Unretained(this)));
+      &NTPSnippetsService::OnDisabledReasonChanged, base::Unretained(this)));
 
   NotifyNewSuggestions();
 }
 
-void NTPSnippetsService::UpdateStateForStatus(DisabledReason disabled_reason) {
+void NTPSnippetsService::OnDisabledReasonChanged(
+    DisabledReason disabled_reason) {
   FOR_EACH_OBSERVER(NTPSnippetsServiceObserver, observers_,
                     NTPSnippetsServiceDisabledReasonChanged(disabled_reason));
 
   switch (disabled_reason) {
     case DisabledReason::NONE:
       EnterState(State::READY, ContentSuggestionsCategoryStatus::AVAILABLE);
       break;
 
     case DisabledReason::HISTORY_SYNC_STATE_UNKNOWN:
       // HistorySync is not initialized yet, so we don't know what the actual
@@ skipping 103 matching lines @@
 }
 
 void NTPSnippetsService::NotifyCategoryStatusChanged() {
   if (observer_) {
     observer_->OnCategoryStatusChanged(ContentSuggestionsCategory::ARTICLES,
                                        category_status_);
   }
 }
 
 }  // namespace ntp_snippets