Extend LargeIconService to fetch missing favicons from a Google server

components/history/core/browser/history_service.h

Index: components/history/core/browser/history_service.h
diff --git a/components/history/core/browser/history_service.h b/components/history/core/browser/history_service.h
index dd6b19aa490f1898e9413cc7fa355269966a4ef5..87cfd26bdaa6d1163d535cd6ec5ec2f507aa8929 100644
--- a/components/history/core/browser/history_service.h
+++ b/components/history/core/browser/history_service.h
@@ -761,6 +761,14 @@ class HistoryService : public syncer::SyncableService, public KeyedService {
                    const GURL& icon_url,
                    const std::vector<SkBitmap>& bitmaps);
 
+  // Same as SetFavicons with two differences: a) the favicon will be initially
+  // set as expired; b) it will be a no-op if there is an existing cached
+  // favicon for *any* type for |page_url|.
+  void SetExpiredFaviconsIfNoneKnown(const GURL& page_url,
+                                     favicon_base::IconType icon_type,
+                                     const GURL& icon_url,
+                                     const std::vector<SkBitmap>& bitmaps);
+
   // Used by the FaviconService to mark the favicon for the page as being out
   // of date.
   void SetFaviconsOutOfDateForPage(const GURL& page_url);