Convert SupervisedUserResourceThrottle to a NavigationThrottle.

chrome/browser/ui/webui/supervised_user_internals_message_handler.h

Index: chrome/browser/ui/webui/supervised_user_internals_message_handler.h
diff --git a/chrome/browser/ui/webui/supervised_user_internals_message_handler.h b/chrome/browser/ui/webui/supervised_user_internals_message_handler.h
index 161b5d0a8eff50da7e136ab227ded157960c7578..247f1220dfddff9396ce8aaa6badd38c28add7ed 100644
--- a/chrome/browser/ui/webui/supervised_user_internals_message_handler.h
+++ b/chrome/browser/ui/webui/supervised_user_internals_message_handler.h
@@ -22,14 +22,13 @@ class SupervisedUserService;
 // The implementation for the chrome://supervised-user-internals page.
 class SupervisedUserInternalsMessageHandler
     : public content::WebUIMessageHandler,
-      public SupervisedUserServiceObserver {
+      public SupervisedUserServiceObserver,
+      public SupervisedUserURLFilter::Observer {
  public:
   SupervisedUserInternalsMessageHandler();
   ~SupervisedUserInternalsMessageHandler() override;
 
  private:
-  class IOThreadHelper;
-
   // content::WebUIMessageHandler:
   void RegisterMessages() override;
 
@@ -51,16 +50,18 @@ class SupervisedUserInternalsMessageHandler
       supervised_user_error_page::FilteringBehaviorReason reason,
       bool uncertain);
 
+  // SupervisedUserURLFilter::Observer:
+  void OnSiteListUpdated() override;
   void OnURLChecked(const GURL& url,
                     SupervisedUserURLFilter::FilteringBehavior behavior,
                     supervised_user_error_page::FilteringBehaviorReason reason,
-                    bool uncertain);
+                    bool uncertain) override;
 
   std::unique_ptr<
       base::CallbackList<void(const base::DictionaryValue*)>::Subscription>
       user_settings_subscription_;
 
-  scoped_refptr<IOThreadHelper> io_thread_helper_;
+  bool is_watching_filter_;

[Marc Treib, 2017/03/28 10:22:58]

Would a ScopedObserver work here?

[mmenke, 2017/03/28 17:55:05]

I'd never heard of that class before.  Seems a bit like over-engineering to me,
but done.

 
   base::WeakPtrFactory<SupervisedUserInternalsMessageHandler> weak_factory_;