[Icons NTP] Refactor large_icon_source to extract the logic shared between desktop and Android to f…

components/favicon/core/favicon_service.h

Index: components/favicon/core/favicon_service.h
diff --git a/components/favicon/core/favicon_service.h b/components/favicon/core/favicon_service.h
index e2379671ceda7ae2b10657f7053d1382971116a8..33aa6e5f4a0dd15bb3ff37149e9214083eb63917 100644
--- a/components/favicon/core/favicon_service.h
+++ b/components/favicon/core/favicon_service.h
@@ -120,7 +120,7 @@ class FaviconService : public KeyedService {
   base::CancelableTaskTracker::TaskId GetLargestRawFaviconForPageURL(
       const GURL& page_url,
       const std::vector<int>& icon_types,
-      int minimum_size_in_pixels,
+      int minimum_size_in_pixel,
       const favicon_base::FaviconRawBitmapCallback& callback,
       base::CancelableTaskTracker* tracker);
 
@@ -131,6 +131,16 @@ class FaviconService : public KeyedService {
       const favicon_base::FaviconResultsCallback& callback,
       base::CancelableTaskTracker* tracker);
 
+  // Requests the best large icon for the page at |page_url| given the requested
+  // |desired_size_in_pixel|. If no good large icon can be found, returns the
+  // fallback style to use, for which the background is set to the dominant
+  // color of a smaller icon when one is available.
+  base::CancelableTaskTracker::TaskId GetLargeIconOrFallbackStyle(
+    const GURL& page_url,
+    int desired_size_in_pixel,
+    const favicon_base::LargeIconCallback& callback,
+    base::CancelableTaskTracker* tracker);
+
   // Set the favicon mappings to |page_url| for |icon_types| in the history
   // database.
   // Sample |icon_urls|:
@@ -240,10 +250,23 @@ class FaviconService : public KeyedService {
       const std::vector<favicon_base::FaviconRawBitmapResult>&
           favicon_bitmap_results);
 
+  // Intermediate callback for GetLargeIconOrFallbackStyle(). Ensures the large
+  // icon is the desired size, if compute the icon fallback style and use it to

[huangs, 2015/04/17 15:30:47]

TYPO: "if compute"

[beaudoin, 2015/04/17 20:29:05]

Done.

+  // invoke |callback|.
+  void RunLargeIconCallback(
+      const favicon_base::LargeIconCallback& callback,
+      int desired_size_in_pixel,
+      const favicon_base::FaviconRawBitmapResult& bitmap_result);
+
   base::hash_set<MissingFaviconURLHash> missing_favicon_urls_;
   history::HistoryService* history_service_;
   FaviconClient* favicon_client_;
 
+  // A pre-populated list of the types of icon files to consider when looking
+  // for large icons. Note: this is simply an optimization over populating an
+  // icon type vector on each request.
+  std::vector<int> large_icon_types_;
+
   DISALLOW_COPY_AND_ASSIGN(FaviconService);
 };