Support interstitials with no primary button

components/security_interstitials/content/security_interstitial_controller_client.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_SECURITY_INTERSTITIALS_CONTENT_SECURITY_INTERSTITIAL_CONTROLLER_CLIENT_H_
 #define COMPONENTS_SECURITY_INTERSTITIALS_CONTENT_SECURITY_INTERSTITIAL_CONTROLLER_CLIENT_H_
 
 #include "base/macros.h"
 #include "components/security_interstitials/core/controller_client.h"
 #include "url/gurl.h"
@@ skipping 30 matching lines @@
   // security_interstitials::ControllerClient overrides.
   void GoBack() override;
   void GoBackAfterNavigationCommitted() override;
   void Proceed() override;
   void Reload() override;
   void OpenUrlInCurrentTab(const GURL& url) override;
   PrefService* GetPrefService() override;
   const std::string& GetApplicationLocale() const override;
   bool CanLaunchDateAndTimeSettings() override;
   void LaunchDateAndTimeSettings() override;
+  bool CanGoBack() override;

[felt, 2017/05/05 00:31:14]

nit: can you move this to be next to GoBack()?

[edwardjung, 2017/05/05 10:24:24]

Done.

 
-protected:
+ protected:
   // security_interstitials::ControllerClient overrides.
   const std::string GetExtendedReportingPrefName() const override;
   content::WebContents* web_contents_;
 
  private:
   content::InterstitialPage* interstitial_page_;
   PrefService* prefs_;
   const std::string app_locale_;
   // The default safe page we should go to if there is no previous page to go
   // back to, e.g. chrome:kChromeUINewTabURL.
   const GURL default_safe_page_;
 
   DISALLOW_COPY_AND_ASSIGN(SecurityInterstitialControllerClient);
 };
 
 }  // namespace security_interstitials
 
 #endif  // COMPONENTS_SECURITY_INTERSTITIALS_CONTENT_SECURITY_INTERSTITIAL_CONTROLLER_CLIENT_H_