Extend LargeIconService to fetch missing favicons from a Google server

components/favicon/core/large_icon_service.h

Index: components/favicon/core/large_icon_service.h
diff --git a/components/favicon/core/large_icon_service.h b/components/favicon/core/large_icon_service.h
index 1370b6a047110ed05cd2eec9dd347652d98be3c3..1ca36f4f38d5f127450e17a010b6aeba40944132 100644
--- a/components/favicon/core/large_icon_service.h
+++ b/components/favicon/core/large_icon_service.h
@@ -5,6 +5,7 @@
 #ifndef COMPONENTS_FAVICON_CORE_LARGE_ICON_SERVICE_H_
 #define COMPONENTS_FAVICON_CORE_LARGE_ICON_SERVICE_H_
 
+#include <string>
 #include <vector>
 
 #include "base/macros.h"
@@ -18,6 +19,10 @@ namespace base {
 class TaskRunner;
 }
 
+namespace image_fetcher {
+class ImageFetcher;
+}
+
 namespace favicon {
 
 class FaviconService;
@@ -28,7 +33,8 @@ class LargeIconService : public KeyedService {
  public:
   LargeIconService(
       FaviconService* favicon_service,
-      const scoped_refptr<base::TaskRunner>& background_task_runner);
+      const scoped_refptr<base::TaskRunner>& background_task_runner,
+      std::unique_ptr<image_fetcher::ImageFetcher> image_fetcher);
   ~LargeIconService() override;
 
   // Requests the best large icon for the page at |page_url|.
@@ -61,6 +67,8 @@ class LargeIconService : public KeyedService {
   // request.
   std::vector<int> large_icon_types_;
 
+  std::unique_ptr<image_fetcher::ImageFetcher> image_fetcher_;
+
   DISALLOW_COPY_AND_ASSIGN(LargeIconService);
 };