Moves WindowCycleList/Controller to ash/common

ash/wm/window_cycle_list.h

-// Copyright 2014 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 ASH_WM_WINDOW_CYCLE_LIST_H_
-#define ASH_WM_WINDOW_CYCLE_LIST_H_
-
-#include <memory>
-#include <vector>
-
-#include "ash/ash_export.h"
-#include "ash/common/wm_window_observer.h"
-#include "ash/wm/window_cycle_controller.h"
-#include "base/macros.h"
-
-namespace views {
-class Label;
-class Widget;
-}
-
-namespace ash {
-
-class ScopedShowWindow;
-class WindowCycleView;
-
-// Tracks a set of Windows that can be stepped through. This class is used by
-// the WindowCycleController.
-class ASH_EXPORT WindowCycleList : public WmWindowObserver {
- public:
-  using WindowList = std::vector<WmWindow*>;
-
-  explicit WindowCycleList(const WindowList& windows);
-  ~WindowCycleList() override;
-
-  bool empty() const { return windows_.empty(); }
-
-  // Cycles to the next or previous window based on |direction|.
-  void Step(WindowCycleController::Direction direction);
-
-  int current_index() const { return current_index_; }
-
- private:
-  friend class WindowCycleControllerTest;
-  const WindowList& windows() const { return windows_; }
-
-  // WmWindowObserver overrides:
-  // There is a chance a window is destroyed, for example by JS code. We need to
-  // take care of that even if it is not intended for the user to close a window
-  // while window cycling.
-  void OnWindowDestroying(WmWindow* window) override;
-
-  // Returns true if the window list overlay should be shown.
-  bool ShouldShowUi();
-
-  // List of weak pointers to windows to use while cycling with the keyboard.
-  // List is built when the user initiates the gesture (i.e. hits alt-tab the
-  // first time) and is emptied when the gesture is complete (i.e. releases the
-  // alt key).
-  WindowList windows_;
-
-  // Current position in the |windows_|. Can be used to query selection depth,
-  // i.e., the position of an active window in a global MRU ordering.
-  int current_index_;
-
-  // Wrapper for the window brought to the front.
-  std::unique_ptr<ScopedShowWindow> showing_window_;
-
-  // The top level View for the window cycle UI. May be null if the UI is not
-  // showing.
-  WindowCycleView* cycle_view_;
-
-  // The widget that hosts the window cycle UI.
-  std::unique_ptr<views::Widget> cycle_ui_widget_;
-
-  DISALLOW_COPY_AND_ASSIGN(WindowCycleList);
-};
-
-}  // namespace ash
-
-#endif  // ASH_WM_WINDOW_CYCLE_LIST_H_