Extend LargeIconService to fetch missing favicons from a Google server

components/favicon/core/BUILD.gn

 # Copyright 2014 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.
 
 static_library("core") {
   sources = [
     "fallback_url_util.cc",
     "fallback_url_util.h",
     "favicon_client.h",
     "favicon_driver.cc",
     "favicon_driver.h",
     "favicon_driver_impl.cc",
     "favicon_driver_impl.h",
     "favicon_driver_observer.h",
     "favicon_handler.cc",
     "favicon_handler.h",
     "favicon_service.cc",
     "favicon_service.h",
     "favicon_url.cc",
     "favicon_url.h",
     "favicon_util.cc",
     "favicon_util.h",
+    "features.cc",
+    "features.h",
     "large_icon_service.cc",
     "large_icon_service.h",
   ]
 
   deps = [
     "//base",
     "//base:i18n",
     "//components/bookmarks/browser",
     "//components/favicon_base",
     "//components/history/core/browser",
@@ skipping 26 matching lines @@
     "//base",
     "//components/favicon_base",
     "//skia",
     "//testing/gtest",
     "//ui/base",
     "//ui/gfx",
     "//ui/gfx:test_support",
     "//url",
   ]
 }