[Night Light] Accessibility: Make ChromeVox speak button status on toggles

ash/system/tiles/tiles_default_view.cc

 // Copyright 2016 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.
 
 #include "ash/system/tiles/tiles_default_view.h"
 
 #include "ash/metrics/user_metrics_action.h"
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/resources/vector_icons/vector_icons.h"
 #include "ash/session/session_controller.h"
@@ skipping 108 matching lines @@
   DCHECK(sender);
   if (sender == settings_button_) {
     Shell::Get()->metrics()->RecordUserMetricsAction(UMA_TRAY_SETTINGS);
     Shell::Get()->system_tray_controller()->ShowSettings();
   } else if (sender == help_button_) {
     Shell::Get()->metrics()->RecordUserMetricsAction(UMA_TRAY_HELP);
     Shell::Get()->system_tray_controller()->ShowHelp();
   } else if (NightLightController::IsFeatureEnabled() &&
              sender == night_light_button_) {
     Shell::Get()->metrics()->RecordUserMetricsAction(UMA_TRAY_NIGHT_LIGHT);
-    Shell::Get()->night_light_controller()->Toggle();
-    night_light_button_->Update();
+    night_light_button_->Toggle();
   } else if (sender == lock_button_) {
     Shell::Get()->metrics()->RecordUserMetricsAction(UMA_TRAY_LOCK_SCREEN);
     chromeos::DBusThreadManager::Get()
         ->GetSessionManagerClient()
         ->RequestLockScreen();
   } else if (sender == power_button_) {
     Shell::Get()->metrics()->RecordUserMetricsAction(UMA_TRAY_SHUT_DOWN);
     Shell::Get()->lock_state_controller()->RequestShutdown(
         ShutdownReason::TRAY_SHUT_DOWN_BUTTON);
   }
 }
 
 views::View* TilesDefaultView::GetHelpButtonView() const {
   return help_button_;
 }
 
 const views::CustomButton* TilesDefaultView::GetShutdownButtonViewForTest()
     const {
   return power_button_;
 }
 
 }  // namespace ash