Eliminate sending NOTIFICATION_TOP_SITES_* from TopSites

components/history/core/browser/top_sites_observer.h

Index: components/history/core/browser/top_sites_observer.h
diff --git a/components/history/core/browser/top_sites_observer.h b/components/history/core/browser/top_sites_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..3dde7f2daee37e5d4a5fe1837c5b29b737a6ffe9
--- /dev/null
+++ b/components/history/core/browser/top_sites_observer.h
@@ -0,0 +1,24 @@
+// 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;
+
+// Interface for observing notifications from TopSites.
+class TopSitesObserver {
+ public:
+  // Is called when TopSites finishes loading.
+  virtual void TopSitesLoaded(history::TopSites* top_sites) = 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;
+};
+
+}  // namespace history
+
+#endif  // COMPONENTS_HISTORY_CORE_BROWSER_TOP_SITES_OBSERVER_H_