Find Favicon in priority of icon_type.

chrome/browser/favicon/favicon_service.h

Index: chrome/browser/favicon/favicon_service.h
diff --git a/chrome/browser/favicon/favicon_service.h b/chrome/browser/favicon/favicon_service.h
index 692a6ebe74e1d570670da09befcfc51ec8658a50..ea6fd35a0fda1f0295c77be5ba1114b08165fc01 100644
--- a/chrome/browser/favicon/favicon_service.h
+++ b/chrome/browser/favicon/favicon_service.h
@@ -67,11 +67,18 @@ class FaviconService : public CancelableRequestProvider,
   typedef base::Callback<void(const chrome::FaviconImageResult&)>
       FaviconImageCallback;
 
-  // Callback for GetRawFavicon() and GetRawFaviconForURL().
+  // Callback for GetRawFavicon(), GetRawFaviconForURL() and
+  // GetLargestRawFavicon().
   // FaviconBitmapResult::bitmap_data is the bitmap in the thumbnail database
-  // for the passed in URL and icon types whose pixel size best matches the
-  // passed in |desired_size_in_dip| and |desired_scale_factor|. Returns an
-  // invalid chrome::FaviconBitmapResult if there are no matches.
+  // for the passed in URL and icon types.
+  // For GetRawFavicon() and GetRawFaviconForURL(), the returned bitmap's pixel
+  // size best matches the passed in |desired_size_in_dip| and
+  // |desired_scale_factor|.
+  // For GetLargestRawFavicon() the returned bitmap is the largest one whose
+  // pixel size is larger than |minimum_size_in_pixels| in the order of
+  // |icon_types|, or the largest one of all |icon_types| if no icon is larger
+  // than |minimum_size_in_pixels|.
+  // Returns an invalid chrome::FaviconBitmapResult if there are no matches.

[michaelbai, 2013/10/18 17:31:49]

Not sure whether we should have the detail description here, it seems
duplicated, should user look for the method's document?

[sky, 2013/10/18 19:29:00]

I agree. I was only thinking you need update the first sentence. Maybe the whole
comment should be nuked and replaced with something like see function for
details on value.

   typedef base::Callback<void(const chrome::FaviconBitmapResult&)>
       FaviconRawCallback;
 
@@ -172,6 +179,15 @@ class FaviconService : public CancelableRequestProvider,
       const FaviconRawCallback& callback,
       CancelableTaskTracker* tracker);
 
+  // See HistoryService::GetLargestFaviconForURL().
+  CancelableTaskTracker::TaskId GetLargestRawFaviconForURL(
+      Profile* profile,
+      const GURL& page_url,
+      const std::vector<int>& icon_types,
+      int minimum_size_in_pixels,
+      const FaviconRawCallback& callback,
+      CancelableTaskTracker* tracker);
+
   CancelableTaskTracker::TaskId GetFaviconForURL(
       const FaviconForURLParams& params,
       const FaviconResultsCallback& callback,