ash: Refresh the tray items, instead of recreating them, when login status changes.

ash/system/bluetooth/tray_bluetooth.cc

Index: ash/system/bluetooth/tray_bluetooth.cc
diff --git a/ash/system/bluetooth/tray_bluetooth.cc b/ash/system/bluetooth/tray_bluetooth.cc
index 6f4dd50fc90faee29532941588f6dc312f155e31..8352457a3bcd2a8ed79ebc5eca763a33eb3354e1 100644
--- a/ash/system/bluetooth/tray_bluetooth.cc
+++ b/ash/system/bluetooth/tray_bluetooth.cc
@@ -250,6 +250,9 @@ void TrayBluetooth::DestroyDetailedView() {
   detailed_.reset();
 }
 
+void TrayBluetooth::UpdateAfterLoginStatusChange(user::LoginStatus status) {
+}
+
 void TrayBluetooth::OnBluetoothRefresh() {
   BluetoothDeviceList list;
   Shell::GetInstance()->tray_delegate()->GetAvailableBluetoothDevices(&list);