cros: Use SessionController to enable system tray settings / notifications tray

ash/test/test_session_controller_client.cc

Index: ash/test/test_session_controller_client.cc
diff --git a/ash/test/test_session_controller_client.cc b/ash/test/test_session_controller_client.cc
index 35fef7e3dc0ed120caba1229a257b92947545607..5d907cc90f596cff321667566c437c027aab17fe 100644
--- a/ash/test/test_session_controller_client.cc
+++ b/ash/test/test_session_controller_client.cc
@@ -104,6 +104,8 @@ void TestSessionControllerClient::AddUserSession(
       AccountId::FromUserEmail(GetUserIdFromEmail(display_email));
   session->display_name = "Über tray Über tray Über tray Über tray";
   session->display_email = display_email;
+  session->should_enable_settings = true;
+  session->should_show_notification_tray = true;
   controller_->UpdateUserSession(std::move(session));
 }