[Thumbnails DB] Allow setting last_requested time when accessing favicons.

components/history/core/browser/thumbnail_database.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_THUMBNAIL_DATABASE_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_THUMBNAIL_DATABASE_H_
 
 #include <vector>
 
 #include "base/gtest_prod_util.h"
@@ skipping 44 matching lines @@
   void RollbackTransaction();
 
   // Vacuums the database. This will cause sqlite to defragment and collect
   // unused space in the file. It can be VERY SLOW.
   void Vacuum();
 
   // Try to trim the cache memory used by the database.  If |aggressively| is
   // true try to trim all unused cache, otherwise trim by half.
   void TrimMemory(bool aggressively);
 
+  // Delete all favicon bitmaps that have not been requested long (i.e. not
+  // after |expiration_threshold|). Furthermore, delete all favicons with no
+  // corresponding bitmap and all mappings with no corresponding favicon.
+  void CleanUnusedFavicons(base::Time expiration_threshold);
+
   // Favicon Bitmaps -----------------------------------------------------------
 
   // Returns true if there are favicon bitmaps for |icon_id|. If
   // |bitmap_id_sizes| is non NULL, sets it to a list of the favicon bitmap ids
   // and their associated pixel sizes for the favicon with |icon_id|.
   // The list contains results for the bitmaps which are cached in the
   // favicon_bitmaps table. The pixel sizes are a subset of the sizes in the
   // 'sizes' field of the favicons table for |icon_id|.
   bool GetFaviconBitmapIDSizes(
       favicon_base::FaviconID icon_id,
       std::vector<FaviconBitmapIDSize>* bitmap_id_sizes);
 
   // Returns true if there are any matched bitmaps for the given |icon_id|. All
   // matched results are returned if |favicon_bitmaps| is not NULL.
   bool GetFaviconBitmaps(favicon_base::FaviconID icon_id,
                          std::vector<FaviconBitmap>* favicon_bitmaps);
 
   // Gets the last updated time, bitmap data, and pixel size of the favicon
-  // bitmap at |bitmap_id|. Returns true if successful.
+  // bitmap at |bitmap_id|. Returns true if successful. The |access_time| is
+  // stored for |bitmap_id| (should be base::Time:Now() in most cases and
+  // base::Time() in incognito profiles to avoid storing the access). The access
+  // times are used to detect that a favicon should be removed if it has not
+  // been used for long.
   bool GetFaviconBitmap(FaviconBitmapID bitmap_id,
+                        base::Time access_time,
                         base::Time* last_updated,
-                        base::Time* last_requested,
                         scoped_refptr<base::RefCountedMemory>* png_icon_data,
                         gfx::Size* pixel_size);
 
   // Adds a bitmap component at |pixel_size| for the favicon with |icon_id|.
   // Only favicons representing a .ico file should have multiple favicon bitmaps
   // per favicon.
   // |icon_data| is the png encoded data.
   // The |time| indicates the access time, and is used to detect when the
   // favicon should be refreshed.
   // |pixel_size| is the pixel dimensions of |icon_data|.
   // Returns the id of the added bitmap or 0 if unsuccessful.
   FaviconBitmapID AddFaviconBitmap(
       favicon_base::FaviconID icon_id,
       const scoped_refptr<base::RefCountedMemory>& icon_data,
       base::Time time,
       const gfx::Size& pixel_size);
 
   // Sets the bitmap data and the last updated time for the favicon bitmap at
   // |bitmap_id|.
   // Returns true if successful.
   bool SetFaviconBitmap(FaviconBitmapID bitmap_id,
                         scoped_refptr<base::RefCountedMemory> bitmap_data,
                         base::Time time);
 
   // Sets the last updated time for the favicon bitmap at |bitmap_id|.
   // Returns true if successful.
   bool SetFaviconBitmapLastUpdateTime(FaviconBitmapID bitmap_id,
                                       base::Time time);
 
-  // Sets the last requested time for the favicon bitmap at |bitmap_id|.
-  // Returns true if successful.
-  bool SetFaviconBitmapLastRequestedTime(FaviconBitmapID bitmap_id,
-                                         base::Time time);
-
   // Deletes the favicon bitmap with |bitmap_id|.
   // Returns true if successful.
   bool DeleteFaviconBitmap(FaviconBitmapID bitmap_id);
 
   // Favicons ------------------------------------------------------------------
 
   // Sets the the favicon as out of date. This will set |last_updated| for all
   // of the bitmaps for |icon_id| to be out of date.
   bool SetFaviconOutOfDate(favicon_base::FaviconID icon_id);
 
@@ skipping 141 matching lines @@
 
   sql::Connection db_;
   sql::MetaTable meta_table_;
 
   HistoryBackendClient* backend_client_;
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_THUMBNAIL_DATABASE_H_