Promotes a handful of members from WmShell to Shell

ui/arc/notification/arc_notification_manager.cc

Index: ui/arc/notification/arc_notification_manager.cc
diff --git a/ui/arc/notification/arc_notification_manager.cc b/ui/arc/notification/arc_notification_manager.cc
index b4619203a7c13360a170dc3f7952d950bf5b83ef..556f18a3860d6483a8f989f663b0778c0d0cd42e 100644
--- a/ui/arc/notification/arc_notification_manager.cc
+++ b/ui/arc/notification/arc_notification_manager.cc
@@ -8,7 +8,7 @@
 #include <utility>
 
 #include "ash/common/system/toast/toast_manager.h"
-#include "ash/common/wm_shell.h"
+#include "ash/shell.h"
 #include "base/memory/ptr_util.h"
 #include "base/stl_util.h"
 #include "base/strings/utf_string_conversions.h"
@@ -245,12 +245,12 @@ void ArcNotificationManager::OnToastPosted(mojom::ArcToastDataPtr data) {
       base::UTF8ToUTF16(data->text.has_value() ? *data->text : std::string()));
   const base::string16 dismiss_text16(base::UTF8ToUTF16(
       data->dismiss_text.has_value() ? *data->dismiss_text : std::string()));
-  ash::WmShell::Get()->toast_manager()->Show(
+  ash::Shell::GetInstance()->toast_manager()->Show(
       ash::ToastData(data->id, text16, data->duration, dismiss_text16));
 }
 
 void ArcNotificationManager::OnToastCancelled(mojom::ArcToastDataPtr data) {
-  ash::WmShell::Get()->toast_manager()->Cancel(data->id);
+  ash::Shell::GetInstance()->toast_manager()->Cancel(data->id);
 }
 
 }  // namespace arc