mash: Add autoclick app.

ash/autoclick/common/autoclick_controller_common_delegate.h

 // 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.
 
 #ifndef ASH_AUTOCLICK_COMMON_AUTOCLICK_CONTROLLER_COMMON_DELEGATE_H
 #define ASH_AUTOCLICK_COMMON_AUTOCLICK_CONTROLLER_COMMON_DELEGATE_H
 
 #include "base/macros.h"
 
 namespace views {
 class Widget;
 }
 
 namespace gfx {
 class Point;
 }
 
 namespace ash {
 
 class AutoclickControllerCommonDelegate {
  public:
   AutoclickControllerCommonDelegate() {}
   virtual ~AutoclickControllerCommonDelegate() {}
 
   // Creates a ring widget at |event_location|. AutoclickControllerCommon

[sky, 2016/09/09 21:42:29]

Update comment? Also, it's not clear why you want to change the ownership
around. Can you explain why ownership should move to the delegate and not the
caller?

[riajiang, 2016/09/12 16:15:46]

Done. I think it makes more sense since the app (the delegate in mash mode) is
the one that is responsible for creating and closing the widget and it owns
AutoclickControllerCommon as well?

   // takes ownership of the created widget.
-  virtual std::unique_ptr<views::Widget> CreateAutoclickRingWidget(
+  virtual views::Widget* CreateAutoclickRingWidget(
       const gfx::Point& event_location) = 0;
 
   // Moves |widget| to |event_location|.
   virtual void UpdateAutoclickRingWidget(views::Widget* widget,
                                          const gfx::Point& event_location) = 0;
 
   // Generates a click with |mouse_event_flags| at |event_location|.
   virtual void DoAutoclick(const gfx::Point& event_location,
                            const int mouse_event_flags) = 0;
 
   virtual void OnAutoclickCanceled() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AutoclickControllerCommonDelegate);
 };
 
 }  // namespace ash
 
 #endif  // ASH_AUTOCLICK_COMMON_AUTOCLICK_CONTROLLER_COMMON_DELEGATE_H