Re-enable AppBannerManagerBrowserTests.

chrome/test/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.
 
 import("//build/config/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//chrome/common/features.gni")
@@ skipping 1298 matching lines @@
       "../browser/apps/guest_view/app_view_browsertest.cc",
       "../browser/apps/guest_view/extension_view/extension_view_browsertest.cc",
       "../browser/apps/guest_view/web_view_browsertest.cc",
       "../browser/apps/service_worker_browsertest.cc",
       "../browser/apps/window_controls_browsertest.cc",
       "../browser/autocomplete/autocomplete_browsertest.cc",
       "../browser/autofill/autofill_browsertest.cc",
       "../browser/autofill/autofill_server_browsertest.cc",
       "../browser/autofill/content_autofill_driver_browsertest.cc",
       "../browser/autofill/form_structure_browsertest.cc",
-
-      # Disabled. Systemic flakiness. See http://crbug.com/660798.
-      # "../browser/banners/app_banner_manager_browsertest.cc",
-
+      "../browser/banners/app_banner_manager_browsertest.cc",
       "../browser/bitmap_fetcher/bitmap_fetcher_browsertest.cc",
       "../browser/browser_encoding_browsertest.cc",
       "../browser/browsing_data/autofill_counter_browsertest.cc",
       "../browser/browsing_data/browsing_data_cache_storage_helper_browsertest.cc",
       "../browser/browsing_data/browsing_data_database_helper_browsertest.cc",
       "../browser/browsing_data/browsing_data_helper_browsertest.h",
       "../browser/browsing_data/browsing_data_indexed_db_helper_browsertest.cc",
       "../browser/browsing_data/browsing_data_local_storage_helper_browsertest.cc",
       "../browser/browsing_data/browsing_data_remover_browsertest.cc",
       "../browser/browsing_data/browsing_data_remover_test_util.cc",
@@ skipping 3723 matching lines @@
       "touch_hud",
       "ui",
     ]
 
     if (is_linux && !is_android) {
       deps += [ "//components/font_service:manifest" ]
       packaged_services += [ "font_service" ]
     }
   }
 }