Purge the App Launcher code from Windows.

chrome/browser/ui/views/app_list/win/activation_tracker_win.h

-// Copyright 2013 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.
-
-#ifndef CHROME_BROWSER_UI_VIEWS_APP_LIST_WIN_ACTIVATION_TRACKER_WIN_H_
-#define CHROME_BROWSER_UI_VIEWS_APP_LIST_WIN_ACTIVATION_TRACKER_WIN_H_
-
-#include "base/macros.h"
-#include "base/timer/timer.h"
-#include "ui/app_list/views/app_list_view_observer.h"
-
-class AppListServiceWin;
-
-// Periodically checks to see if an AppListView has lost focus using a timer.
-class ActivationTrackerWin : public app_list::AppListViewObserver {
- public:
-  explicit ActivationTrackerWin(AppListServiceWin* service);
-  ~ActivationTrackerWin() override;
-
-  // app_list::AppListViewObserver:
-  void OnActivationChanged(views::Widget* widget, bool active) override;
-
-  void OnViewHidden();
-
- private:
-  // Dismisses the app launcher if it has lost focus and the user is not trying
-  // to pin it.
-  void MaybeDismissAppList();
-
-  // Determines whether the app launcher should be dismissed. This should be
-  // called at most once per timer tick, as it is not idempotent (if the taskbar
-  // is focused, it waits until it has been called twice before dismissing the
-  // app list).
-  bool ShouldDismissAppList();
-
-  AppListServiceWin* service_;  // Weak. Owns this.
-
-  // Records whether, on the previous timer tick, the taskbar had focus without
-  // the right mouse button being down. We allow the taskbar to have focus for
-  // one tick before dismissing the app list. This allows the app list to be
-  // kept visible if the taskbar is seen briefly without the right mouse button
-  // down, but not if this happens for two consecutive ticks.
-  bool taskbar_has_focus_;
-
-  // Timer used to check if the taskbar or app list is active. Using a timer
-  // means we don't need to hook Windows, which is apparently not possible
-  // since Vista (and is not nice at any time).
-  base::RepeatingTimer timer_;
-
-  DISALLOW_COPY_AND_ASSIGN(ActivationTrackerWin);
-};
-
-#endif  // CHROME_BROWSER_UI_VIEWS_APP_LIST_WIN_ACTIVATION_TRACKER_WIN_H_