It is time.

ui/views/focus/widget_focus_manager.cc

-// Copyright (c) 2011 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 "ui/views/focus/widget_focus_manager.h"
-
-#include "base/memory/singleton.h"
-
-namespace views {
-
-// WidgetFocusManager ----------------------------------------------------------
-
-// static
-WidgetFocusManager* WidgetFocusManager::GetInstance() {
-  return Singleton<WidgetFocusManager>::get();
-}
-
-void WidgetFocusManager::AddFocusChangeListener(
-    WidgetFocusChangeListener* listener) {
-  focus_change_listeners_.AddObserver(listener);
-}
-
-void WidgetFocusManager::RemoveFocusChangeListener(
-    WidgetFocusChangeListener* listener) {
-  focus_change_listeners_.RemoveObserver(listener);
-}
-
-void WidgetFocusManager::OnWidgetFocusEvent(gfx::NativeView focused_before,
-                                            gfx::NativeView focused_now) {
-  if (enabled_ && focused_before != focused_now) {
-    FOR_EACH_OBSERVER(WidgetFocusChangeListener, focus_change_listeners_,
-                      OnNativeFocusChange(focused_before, focused_now));
-  }
-}
-
-WidgetFocusManager::WidgetFocusManager() : enabled_(true) {}
-
-WidgetFocusManager::~WidgetFocusManager() {}
-
-// AutoNativeNotificationDisabler ----------------------------------------------
-
-AutoNativeNotificationDisabler::AutoNativeNotificationDisabler() {
-  WidgetFocusManager::GetInstance()->DisableNotifications();
-}
-
-AutoNativeNotificationDisabler::~AutoNativeNotificationDisabler() {
-  WidgetFocusManager::GetInstance()->EnableNotifications();
-}
-
-}  // namespace views