Update all bookmarks which use an icon URL when a favicon's bitmap is updated

components/history/core/browser/history_backend.h

 // Copyright (c) 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.
 
 #ifndef COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
 
 #include <set>
 #include <string>
 #include <utility>
@@ skipping 102 matching lines @@
     // Sets the in-memory history backend. The in-memory backend is created by
     // the main backend. For non-unit tests, this happens on the background
     // thread. It is to be used on the main thread, so this would transfer
     // it to the history service. Unit tests can override this behavior.
     //
     // This function is NOT guaranteed to be called. If there is an error,
     // there may be no in-memory database.
     virtual void SetInMemoryBackend(
         scoped_ptr<InMemoryHistoryBackend> backend) = 0;
 
-    // Notify HistoryService that some URLs favicon changed that will forward
-    // the events to the FaviconChangedObservers in the correct thread.
-    virtual void NotifyFaviconChanged(const std::set<GURL>& urls) = 0;
+    // Notify HistoryService that the favicons for the given page URLs (e.g.
+    // http://www.google.com) and the given icon URL (e.g.
+    // http://www.google.com/favicon.ico) have changed. HistoryService notifies
+    // any registered callbacks. It is valid to call NotifyFaviconsChanged()
+    // with non-empty |page_urls| and an empty |icon_url| and vice versa.
+    virtual void NotifyFaviconsChanged(const std::set<GURL>& page_urls,
+                                       const GURL& icon_url) = 0;
 
     // Notify HistoryService that the user is visiting an URL. The event will
     // be forwarded to the HistoryServiceObservers in the correct thread.
     virtual void NotifyURLVisited(ui::PageTransition transition,
                                   const URLRow& row,
                                   const RedirectList& redirects,
                                   base::Time visit_time) = 0;
 
     // Notify HistoryService that some URLs have been modified. The event will
     // be forwarded to the HistoryServiceObservers in the correct thread.
@@ skipping 361 matching lines @@
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, MergeFaviconPageURLNotInDB);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, MergeFaviconPageURLInDB);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, MergeFaviconMaxFaviconsPerPage);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            MergeFaviconIconURLMappedToDifferentPageURL);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            MergeFaviconMaxFaviconBitmapsPerIconURL);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            MergeIdenticalFaviconDoesNotChangeLastUpdatedTime);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
+                           FaviconChangedNotificationNewFavicon);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
+                           FaviconChangedNotificationBitmapDataChanged);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
+                           FaviconChangedNotificationIconMappingChanged);
+  FRIEND_TEST_ALL_PREFIXES(
+      HistoryBackendTest,
+      FaviconChangedNotificationIconMappingAndBitmapDataChanged);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
+                           FaviconChangedNotificationsMergeCopy);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, NoFaviconChangedNotifications);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            UpdateFaviconMappingsAndFetchMultipleIconTypes);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, GetFaviconsFromDBEmpty);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            GetFaviconsFromDBNoFaviconBitmaps);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            GetFaviconsFromDBSelectClosestMatch);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, GetFaviconsFromDBIconType);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, GetFaviconsFromDBExpired);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            UpdateFaviconMappingsAndFetchNoDB);
@@ skipping 193 matching lines @@
       const GURL& page_url,
       favicon_base::IconType icon_type,
       const std::vector<favicon_base::FaviconID>& icon_ids);
 
   // Returns all the page URLs in the redirect chain for |page_url|. If there
   // are no known redirects for |page_url|, returns a vector with |page_url|.
   void GetCachedRecentRedirects(const GURL& page_url,
                                 RedirectList* redirect_list);
 
   // Send notification that the favicon has changed for |page_url| and all its
-  // redirects.
+  // redirects. This should be called if the mapping between the page URL
+  // (e.g. http://www.google.com) and the icon URL (e.g.
+  // http://www.google.com/favicon.ico) has changed.
   void SendFaviconChangedNotificationForPageAndRedirects(const GURL& page_url);
 
+  // Send notification that the bitmap data for the favicon at |icon_url| has
+  // changed. Sending this notification is important because the favicon at
+  // |icon_url| may be mapped to hundreds of page URLs.
+  void SendFaviconChangedNotificationForIconURL(const GURL& icon_url);
+
   // Generic stuff -------------------------------------------------------------
 
   // Processes the next scheduled HistoryDBTask, scheduling this method
   // to be invoked again if there are more tasks that need to run.
   void ProcessDBTaskImpl();
 
   // HistoryBackendNotifier:
-  void NotifyFaviconChanged(const std::set<GURL>& urls) override;
+  void NotifyFaviconsChanged(const std::set<GURL>& page_urls,
+                             const GURL& icon_url) override;
   void NotifyURLVisited(ui::PageTransition transition,
                         const URLRow& row,
                         const RedirectList& redirects,
                         base::Time visit_time) override;
   void NotifyURLsModified(const URLRows& rows) override;
   void NotifyURLsDeleted(bool all_history,
                          bool expired,
                          const URLRows& rows,
                          const std::set<GURL>& favicon_urls) override;
 
@@ skipping 97 matching lines @@
 
   // List of observers
   base::ObserverList<HistoryBackendObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(HistoryBackend);
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_