Load offline page if reading list entry takes more than 1s to load.

ios/chrome/browser/BUILD.gn

 # 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.
 
 import("//build/config/features.gni")
 import("//ios/web/js_compile.gni")
 import("//third_party/protobuf/proto_library.gni")
 
 declare_args() {
   google_test_gaia_client_id = ""
@@ skipping 342 matching lines @@
     "reading_list/reading_list_model_bridge_observer.mm",
     "reading_list/reading_list_model_factory.cc",
     "reading_list/reading_list_model_factory.h",
     "reading_list/reading_list_model_impl.cc",
     "reading_list/reading_list_model_impl.h",
     "reading_list/reading_list_model_observer.h",
     "reading_list/reading_list_model_observer.h",
     "reading_list/reading_list_model_storage.h",
     "reading_list/reading_list_model_storage_defaults.h",
     "reading_list/reading_list_model_storage_defaults.mm",
+    "reading_list/reading_list_web_state_observer.h",
+    "reading_list/reading_list_web_state_observer.mm",
     "reading_list/url_downloader.cc",
     "reading_list/url_downloader.h",
     "root_coordinator.h",
     "root_coordinator.mm",
     "search_engines/search_engines_util.cc",
     "search_engines/search_engines_util.h",
     "search_engines/template_url_service_client_impl.cc",
     "search_engines/template_url_service_client_impl.h",
     "search_engines/template_url_service_factory.cc",
     "search_engines/template_url_service_factory.h",
@@ skipping 484 matching lines @@
     "//ios/public/provider/chrome/browser",
     "//ios/public/provider/chrome/browser:test_support",
     "//ios/web",
     "//net:test_support",
     "//testing/gmock",
     "//testing/gtest",
     "//ui/base",
     "//url",
   ]
 }