Add a SupervisedUserServiceObserver.

chrome/browser/supervised_user/supervised_user_interstitial.h

 // Copyright 2014 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_SUPERVISED_USER_SUPERVISED_USER_INTERSTITIAL_H_
 #define CHROME_BROWSER_SUPERVISED_USER_SUPERVISED_USER_INTERSTITIAL_H_
 
 #include <string>
 
 #include "base/callback.h"
-#include "base/prefs/pref_change_registrar.h"
+#include "chrome/browser/supervised_user/supervised_user_service_observer.h"
 #include "content/public/browser/interstitial_page_delegate.h"
 #include "url/gurl.h"
 
 namespace content {
 class InterstitialPage;
 class WebContents;
 }
 
 // Delegate for an interstitial page when a page is blocked for a supervised
 // user because it is on a blacklist (in "allow everything" mode) or not on any
 // whitelist (in "allow only specified sites" mode).
-class SupervisedUserInterstitial : public content::InterstitialPageDelegate {
+class SupervisedUserInterstitial : public content::InterstitialPageDelegate,
+                                   public SupervisedUserServiceObserver {
  public:
   static void Show(content::WebContents* web_contents,
                    const GURL& url,
                    const base::Callback<void(bool)>& callback);
 
  private:
   SupervisedUserInterstitial(content::WebContents* web_contents,
                              const GURL& url,
                              const base::Callback<void(bool)>& callback);
   virtual ~SupervisedUserInterstitial();
 
   bool Init();
 
   // InterstitialPageDelegate implementation.
   virtual std::string GetHTMLContents() OVERRIDE;
   virtual void CommandReceived(const std::string& command) OVERRIDE;
   virtual void OnProceed() OVERRIDE;
   virtual void OnDontProceed() OVERRIDE;
 
+  // SupervisedUserServiceObserver implementation.
+  virtual void OnURLFilterChanged() OVERRIDE;
+
   // Returns whether the blocked URL is now allowed. Called initially before the
   // interstitial is shown (to catch race conditions), or when the URL filtering
   // prefs change.
   bool ShouldProceed();
 
-  void OnFilteringPrefsChanged();
   void DispatchContinueRequest(bool continue_request);
 
   // Owns the interstitial, which owns us.
   content::WebContents* web_contents_;
 
   content::InterstitialPage* interstitial_page_;  // Owns us.
 
-  PrefChangeRegistrar pref_change_registrar_;
-
   GURL url_;
 
   base::Callback<void(bool)> callback_;
 
   DISALLOW_COPY_AND_ASSIGN(SupervisedUserInterstitial);
 };
 
 #endif  // CHROME_BROWSER_SUPERVISED_USER_SUPERVISED_USER_INTERSTITIAL_H_