Topsites become keyedService based.

components/history/core/browser/top_sites_observer.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 COMPONENTS_HISTORY_CORE_BROWSER_TOP_SITES_OBSERVER_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_TOP_SITES_OBSERVER_H_
 
 namespace history {
-class TopSites;
+class TopSitesProvider;
 
 // Interface for observing notifications from TopSites.
 class TopSitesObserver {
  public:
   // Is called when TopSites finishes loading.
-  virtual void TopSitesLoaded(history::TopSites* top_sites) = 0;
+  virtual void TopSitesLoaded(
+      history::TopSitesProvider* top_sites_provider) = 0;
 
   // Is called when either one of the most visited urls
   // changed, or one of the images changes.
-  virtual void TopSitesChanged(history::TopSites* top_sites) = 0;
+  virtual void TopSitesChanged(
+      history::TopSitesProvider* top_sites_provider) = 0;
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_TOP_SITES_OBSERVER_H_