Revert of Supervised Users: Create ResourceThrottle only if filtering is enabled

chrome/browser/supervised_user/supervised_user_url_filter.h

Index: chrome/browser/supervised_user/supervised_user_url_filter.h
diff --git a/chrome/browser/supervised_user/supervised_user_url_filter.h b/chrome/browser/supervised_user/supervised_user_url_filter.h
index e11c50cc6159d9a3379319d7db2e1365ae53590d..0b34d37f47912678b09440bfab1f78c60623197f 100644
--- a/chrome/browser/supervised_user/supervised_user_url_filter.h
+++ b/chrome/browser/supervised_user/supervised_user_url_filter.h
@@ -61,11 +61,7 @@
 
   class Observer {
    public:
-    // Called whenever the filter changes.
-    // TODO(treib,bauerb): Rename to OnURLFilterUpdated.
     virtual void OnSiteListUpdated() = 0;
-    // Called whenever a check started via
-    // GetFilteringBehaviorForURLWithAsyncChecks completes.
     virtual void OnURLChecked(
         const GURL& url,
         FilteringBehavior behavior,
@@ -110,13 +106,6 @@
   static bool HostMatchesPattern(const std::string& canonical_host,
                                  const std::string& pattern);
 
-  // Returns whether the filter is enabled. If this is false, all URL checks
-  // will return ALLOW.
-  bool enabled() const { return enabled_; }
-
-  // Enables or disables the filter. Notifies observers if the state changed.
-  void SetEnabled(bool enabled);
-
   // Returns the filtering behavior for a given URL, based on the default
   // behavior and whether it is on a site list.
   FilteringBehavior GetFilteringBehaviorForURL(const GURL& url) const;
@@ -209,10 +198,6 @@
   // This is mutable to allow notification in const member functions.
   mutable base::ObserverList<Observer> observers_;
 
-  // Whether this filter is enabled. True for supervised user profiles, false
-  // otherwise.
-  bool enabled_;
-
   FilteringBehavior default_behavior_;
   std::unique_ptr<Contents> contents_;