[Device Discovery] Make DialRegistry a Singleton

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 4366 matching lines @@
     ]
   }
 
   if (enable_media_router) {
     sources += [
       "../browser/media/cast_remoting_connector_unittest.cc",
       "../browser/media/router/browser_presentation_connection_proxy_unittest.cc",
       "../browser/media/router/create_presentation_connection_request_unittest.cc",
       "../browser/media/router/discovery/dial/device_description_fetcher_unittest.cc",
       "../browser/media/router/discovery/dial/dial_device_data_unittest.cc",
+      "../browser/media/router/discovery/dial/dial_registry_factory_unittest.cc",
       "../browser/media/router/discovery/dial/dial_registry_unittest.cc",
       "../browser/media/router/discovery/dial/dial_service_unittest.cc",
       "../browser/media/router/discovery/media_sink_internal_unittest.cc",
       "../browser/media/router/issue_manager_unittest.cc",
       "../browser/media/router/issue_unittest.cc",
       "../browser/media/router/media_route_unittest.cc",
       "../browser/media/router/media_router_base_unittest.cc",
       "../browser/media/router/media_router_dialog_controller_unittest.cc",
       "../browser/media/router/media_router_factory_unittest.cc",
       "../browser/media/router/media_router_metrics_unittest.cc",
@@ skipping 790 matching lines @@
 }
 
 if (is_win) {
   loadable_module("conflicts_dll") {
     testonly = true
     sources = [
       "conflicts/conflicts_dll.cc",
     ]
   }
 }