Add baked-in favicons for default popular sites on NTP

components/ntp_tiles/popular_sites.h

 // Copyright 2015 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_NTP_TILES_POPULAR_SITES_H_
 #define COMPONENTS_NTP_TILES_POPULAR_SITES_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 19 matching lines @@
          const GURL& large_icon_url,
          const GURL& thumbnail_url);
     Site(const Site& other);
     ~Site();
 
     base::string16 title;
     GURL url;
     GURL favicon_url;
     GURL large_icon_url;
     GURL thumbnail_url;
+    int default_icon_resource;  // < 0 if there is none. Used for popular sites.
   };
 
   using SitesVector = std::vector<Site>;
   using FinishedCallback = base::Callback<void(bool /* success */)>;
 
   virtual ~PopularSites() = default;
 
   // May start the process of retrieving popular sites. If an actual download
   // gets triggered, returns true and invokes |callback| with the result, on the
   // same thread as the caller. Never invokes |callback| before returning
@@ skipping 16 matching lines @@
   virtual GURL GetLastURLFetched() const = 0;
   virtual GURL GetURLToFetch() = 0;
   virtual std::string GetCountryToFetch() = 0;
   virtual std::string GetVersionToFetch() = 0;
   virtual const base::ListValue* GetCachedJson() = 0;
 };
 
 }  // namespace ntp_tiles
 
 #endif  // COMPONENTS_NTP_TILES_POPULAR_SITES_H_