Remove TopSites notification in favor of Observers

chrome/browser/jumplist_win.cc

 // Copyright 2012 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/jumplist_win.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/files/file_util.h"
@@ skipping 238 matching lines @@
   icon_dir_ = profile_->GetPath().Append(chrome::kJumpListIconDirname);
   use_profiles_category_ = HasProfilesJumplistExperiment();
 
   history::TopSites* top_sites = profile_->GetTopSites();
   if (top_sites) {
     // TopSites updates itself after a delay. This is especially noticable when
     // your profile is empty. Ask TopSites to update itself when jumplist is
     // initialized.
     top_sites->SyncWithHistory();
     registrar_.reset(new content::NotificationRegistrar);
-    // Register for notification when TopSites changes so that we can update
-    // ourself.
-    registrar_->Add(this, chrome::NOTIFICATION_TOP_SITES_CHANGED,
-                    content::Source<history::TopSites>(top_sites));
+    // Register as TopSitesObserver so that we can update ourselves when the
+    // TopSites changes.
+    top_sites->AddObserver(this);
     // Register for notification when profile is destroyed to ensure that all
     // observers are detatched at that time.
     registrar_->Add(this, chrome::NOTIFICATION_PROFILE_DESTROYED,
                     content::Source<Profile>(profile_));
   }
   tab_restore_service->AddObserver(this);
   pref_change_registrar_.reset(new PrefChangeRegistrar);
   pref_change_registrar_->Init(profile_->GetPrefs());
   pref_change_registrar_->Add(
       prefs::kIncognitoModeAvailability,
@@ skipping 13 matching lines @@
 }
 
 // static
 bool JumpList::Enabled() {
   return JumpListUpdater::IsEnabled();
 }
 
 void JumpList::Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) {
-  switch (type) {
-    case chrome::NOTIFICATION_TOP_SITES_CHANGED: {
-      // Most visited urls changed, query again.
-      history::TopSites* top_sites = profile_->GetTopSites();
-      if (top_sites) {
-        top_sites->GetMostVisitedURLs(
-            base::Bind(&JumpList::OnMostVisitedURLsAvailable,
-                       weak_ptr_factory_.GetWeakPtr()), false);
-      }
-      break;
-    }
-    case chrome::NOTIFICATION_PROFILE_DESTROYED: {
-      // Profile was destroyed, do clean-up.
-      Terminate();
-      break;
-    }
-    default:
-      NOTREACHED() << "Unexpected notification type.";
-  }
+  DCHECK_EQ(type, chrome::NOTIFICATION_PROFILE_DESTROYED);
+  // Profile was destroyed, do clean-up.
+  Terminate();
 }
 
 void JumpList::CancelPendingUpdate() {
   if (task_id_ != base::CancelableTaskTracker::kBadTaskId) {
     cancelable_task_tracker_.TryCancel(task_id_);
     task_id_ = base::CancelableTaskTracker::kBadTaskId;
   }
 }
 
 void JumpList::Terminate() {
   CancelPendingUpdate();
   if (profile_) {
     TabRestoreService* tab_restore_service =
         TabRestoreServiceFactory::GetForProfile(profile_);
     if (tab_restore_service)
       tab_restore_service->RemoveObserver(this);
+    history::TopSites* top_sites = profile_->GetTopSites();
+    if (top_sites)
+      top_sites->RemoveObserver(this);
     registrar_.reset();
     pref_change_registrar_.reset();
   }
   profile_ = NULL;
 }
 
 void JumpList::OnMostVisitedURLsAvailable(
     const history::MostVisitedURLList& data) {
   // If we have a pending favicon request, cancel it here (it is out of date).
   CancelPendingUpdate();
@@ skipping 267 matching lines @@
       link->set_icon_data(avatar.AsBitmap());
       new_profile_switcher.push_back(link);
     }
   }
 
   {
     base::AutoLock auto_lock(list_lock_);
     new_profile_switcher.swap(profile_switcher_);
   }
 }
+
+void JumpList::TopSitesLoaded(history::TopSites* top_sites) {
+}
+
+void JumpList::TopSitesChanged(history::TopSites* top_sites) {
+  // Most visited urls changed, query again.
+  history::TopSites* top_sites = profile_->GetTopSites();
+  if (top_sites) {
+    top_sites->GetMostVisitedURLs(
+        base::Bind(&JumpList::OnMostVisitedURLsAvailable,
+                   weak_ptr_factory_.GetWeakPtr()),
+        false);
+  }
+}