cros: Laser pointer fades out on release, do not cover palette.

ash/laser/laser_pointer_view.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_LASER_LASER_POINTER_VIEW_H_
 #define ASH_LASER_LASER_POINTER_VIEW_H_
 
 #include <memory>
 
 #include "ash/laser/laser_pointer_points.h"
@@ skipping 17 matching lines @@
 // LaserPointerView displays the palette tool laser pointer. It draws the laser,
 // which consists of a point where the mouse cursor should be, as well as a
 // trail of lines to help users track.
 class LaserPointerView : public views::View {
  public:
   LaserPointerView(base::TimeDelta life_duration, aura::Window* root_window);
   ~LaserPointerView() override;
 
   void AddNewPoint(const gfx::Point& new_point);
   void Stop();
+  void SetIsFadingAway(bool is_fading);

[jdufault, 2016/09/23 23:59:20]

Rename to set_is_fading_away. Trival methods (like this one) should be inlined
as well.

[sammiequon, 2016/09/26 19:30:38]

Done.

+  bool GetIsFadingAway() const;

[jdufault, 2016/09/23 23:59:20]

Rename to is_fading_away() and inline the definition.

[sammiequon, 2016/09/26 19:30:38]

Done.

+
   aura::Window* GetRootWindow();
 
   // Reparents the widget if needed.
   void ReparentWidget(aura::Window* new_root_window);
 
  private:
   friend class LaserPointerControllerTestApi;
 
   // view::View:
   void OnPaint(gfx::Canvas* canvas) override;
 
   LaserPointerPoints laser_points_;
   std::unique_ptr<views::Widget> widget_;
+  // |is_fading_away_| determines whether the laser pointer view should accept
+  // points normally, or just advance the |laser_points_| time so that current
+  // points start fading away. This should be set to true when the view is about
+  // to be destroyed, such as when the stylus is released.
+  bool is_fading_away_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(LaserPointerView);
 };
 
 }  // namespace ash
 
 #endif  // ASH_LASER_LASER_POINTER_VIEW_H_