Refactor HistoryService to not send NOTIFICATION_FAVICON_CHANGED

chrome/browser/bookmarks/chrome_bookmark_client.h

Index: chrome/browser/bookmarks/chrome_bookmark_client.h
diff --git a/chrome/browser/bookmarks/chrome_bookmark_client.h b/chrome/browser/bookmarks/chrome_bookmark_client.h
index 30646be27b787c205741aff18f18fdce39fe325e..586aad997e341291223fe06709b2abdf41e500c2 100644
--- a/chrome/browser/bookmarks/chrome_bookmark_client.h
+++ b/chrome/browser/bookmarks/chrome_bookmark_client.h
@@ -5,21 +5,22 @@
 #ifndef CHROME_BROWSER_BOOKMARKS_CHROME_BOOKMARK_CLIENT_H_
 #define CHROME_BROWSER_BOOKMARKS_CHROME_BOOKMARK_CLIENT_H_
 
+#include <set>
 #include <vector>
 
+#include "base/callback_list.h"
 #include "base/deferred_sequenced_task_runner.h"
 #include "base/macros.h"
 #include "components/bookmarks/browser/base_bookmark_model_observer.h"
 #include "components/bookmarks/browser/bookmark_client.h"
 #include "components/policy/core/browser/managed_bookmarks_tracker.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
 
 class BookmarkModel;
+class GURL;
+class HistoryService;
 class Profile;
 
 class ChromeBookmarkClient : public bookmarks::BookmarkClient,
-                             public content::NotificationObserver,
                              public BaseBookmarkModelObserver {
  public:
   explicit ChromeBookmarkClient(Profile* profile);
@@ -60,11 +61,6 @@ class ChromeBookmarkClient : public bookmarks::BookmarkClient,
   virtual bool CanSyncNode(const BookmarkNode* node) OVERRIDE;
   virtual bool CanBeEditedByUser(const BookmarkNode* node) OVERRIDE;
 
-  // content::NotificationObserver:
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
  private:
   // BaseBookmarkModelObserver:
   virtual void BookmarkModelChanged() OVERRIDE;
@@ -91,7 +87,9 @@ class ChromeBookmarkClient : public bookmarks::BookmarkClient,
 
   Profile* profile_;
 
-  content::NotificationRegistrar registrar_;
+  scoped_ptr<base::CallbackList<
+      void(HistoryService*, const std::set<GURL>&)>::Subscription>
+      favicon_changed_subscription_;
 
   // Pointer to the BookmarkModel. Will be non-NULL from the call to Init to
   // the call to Shutdown. Must be valid for the whole interval.