Fix ntp-tiles-internals crash in incognito mode

chrome/browser/ui/webui/ntp_tiles_internals_ui.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 "chrome/browser/ui/webui/ntp_tiles_internals_ui.h"
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "chrome/browser/favicon/favicon_service_factory.h"
 #include "chrome/browser/history/top_sites_factory.h"
@@ skipping 24 matching lines @@
     : public content::WebUIMessageHandler,
       public ntp_tiles::NTPTilesInternalsMessageHandlerClient {
  public:
   ChromeNTPTilesInternalsMessageHandlerClient() {}
 
  private:
   // content::WebUIMessageHandler:
   void RegisterMessages() override;
 
   // ntp_tiles::NTPTilesInternalsMessageHandlerClient
+  bool SupportsNTPTiles() override;
   bool DoesSourceExist(ntp_tiles::NTPTileSource source) override;
   std::unique_ptr<ntp_tiles::MostVisitedSites> MakeMostVisitedSites() override;
   std::unique_ptr<ntp_tiles::PopularSites> MakePopularSites() override;
   PrefService* GetPrefs() override;
   void RegisterMessageCallback(
       const std::string& message,
       const base::Callback<void(const base::ListValue*)>& callback) override;
   void CallJavascriptFunctionVector(
       const std::string& name,
       const std::vector<const base::Value*>& values) override;
 
   ntp_tiles::NTPTilesInternalsMessageHandler handler_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeNTPTilesInternalsMessageHandlerClient);
 };
 
 void ChromeNTPTilesInternalsMessageHandlerClient::RegisterMessages() {
   handler_.RegisterMessages(this);
 }
 
+bool ChromeNTPTilesInternalsMessageHandlerClient::SupportsNTPTiles() {
+  Profile* profile = Profile::FromWebUI(web_ui());
+  return !(profile->IsGuestSession() || profile->IsOffTheRecord());
+}
+
 bool ChromeNTPTilesInternalsMessageHandlerClient::DoesSourceExist(
     ntp_tiles::NTPTileSource source) {
   switch (source) {
     case ntp_tiles::NTPTileSource::TOP_SITES:
     case ntp_tiles::NTPTileSource::SUGGESTIONS_SERVICE:
     case ntp_tiles::NTPTileSource::WHITELIST:
       return true;
     case ntp_tiles::NTPTileSource::POPULAR:
 #if defined(OS_ANDROID)
       return true;
@@ skipping 51 matching lines @@
 
 NTPTilesInternalsUI::NTPTilesInternalsUI(content::WebUI* web_ui)
     : WebUIController(web_ui) {
   content::WebUIDataSource::Add(Profile::FromWebUI(web_ui),
                                 CreateNTPTilesInternalsHTMLSource());
   web_ui->AddMessageHandler(
       base::MakeUnique<ChromeNTPTilesInternalsMessageHandlerClient>());
 }
 
 NTPTilesInternalsUI::~NTPTilesInternalsUI() {}