Adds support for saving favicon size into history database.

chrome/browser/history/select_favicon_frames.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 CHROME_BROWSER_HISTORY_SELECT_FAVICON_FRAMES_H_
 #define CHROME_BROWSER_HISTORY_SELECT_FAVICON_FRAMES_H_
 
 #include <vector>
 
+#include "chrome/browser/history/history_types.h"
 #include "ui/base/layout.h"
 
 class SkBitmap;
 
 namespace gfx {
 class ImageSkia;
 }
 
+// Score which is smaller than the minimum score returned by
+// SelectFaviconFrames() or SelectFaviconBitmapIDs().
+extern const float kSelectFaviconFramesInvalidScore;
+
 // Takes a list of all bitmaps found in a .ico file, and creates an
-// ImageSkia that's desired_size x desired_size pixels big. This
+// ImageSkia that's |desired_size| x |desired_size| DIP big. This
 // function adds a representation at every desired scale factor.
-// If desired_size is 0, the largest bitmap is returned unmodified.
-// If score is non-NULL, it receive a score between 0 (bad) and 1 (good)
+// If |desired_size| is 0, the largest bitmap is returned unmodified.
+// If score is non-NULL, it receives a score between 0 (bad) and 1 (good)
 // that describes how well |bitmaps| were able to produce an image at
 // |desired_size| for |scale_factors|.
 // The score is arbitrary, but it's best for exact size matches,
 // and gets worse the more resampling needs to happen.
 gfx::ImageSkia SelectFaviconFrames(
     const std::vector<SkBitmap>& bitmaps,
     const std::vector<ui::ScaleFactor>& scale_factors,
     int desired_size,
     float* score);
 
+// Takes a list of all history::FaviconBitmapIDSize for a favicon and returns
+// the FaviconBitmapIDs (in |filtered_favicon_bitmap_ids|) whose bitmap data
+// should be fetched in order to create an ImageSkia that's |desired_size| x
+// |desired_size| DIP big.
+// If |desired_size| is 0, the FaviconBitmapID with the largest size is
+// returned. If score is non-NULL, it receives a score between 0 (bad) and
+// 1 (good) that describes how well |filtered_favicon_bitmap_ids| will
+// produce an image at |desired_size| for |scale_factors|. The score is
+// arbitrary, but it's best for exact size matches, and gets worse the
+// more resampling needs to happen.
+// TODO(pkotwicz): Remove need to pass in |scale_factors|.
+void SelectFaviconBitmapIDs(
+    const std::vector<history::FaviconBitmapIDSize>& bitmap_id_sizes,
+    const std::vector<ui::ScaleFactor>& scale_factors,
+    int desired_size,
+    std::vector<history::FaviconBitmapID>* filtered_favicon_bitmap_ids,
+    float* score);
+
 #endif  // CHROME_BROWSER_HISTORY_SELECT_FAVICON_FRAMES_H_