Ash Window Cycle UI - add initial show delay and fade in.

ash/common/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_COMMON_WM_WINDOW_CYCLE_LIST_H_
 #define ASH_COMMON_WM_WINDOW_CYCLE_LIST_H_
 
 #include <memory>
 #include <vector>
 
 #include "ash/ash_export.h"
 #include "ash/common/wm/window_cycle_controller.h"
 #include "ash/common/wm_window_observer.h"
 #include "base/macros.h"
+#include "base/timer/timer.h"
 
 namespace views {
 class Label;
 class Widget;
 }
 
 namespace ash {
 
 class ScopedShowWindow;
 class WindowCycleView;
@@ skipping 20 matching lines @@
 
   // 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();
 
+  // Initializes and shows |cycle_view_|.
+  void InitWindowCycleView();
+
   // 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_;
 
+  // A timer to delay showing the UI. Quick Alt+Tab should not flash a UI.
+  base::OneShotTimer show_ui_timer_;
+
   DISALLOW_COPY_AND_ASSIGN(WindowCycleList);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_WM_WINDOW_CYCLE_LIST_H_