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

ash/laser/laser_pointer_controller.h

Index: ash/laser/laser_pointer_controller.h
diff --git a/ash/laser/laser_pointer_controller.h b/ash/laser/laser_pointer_controller.h
index 21697ca3ac0a8ce023983ffe66f3066b39250cde..7a92624860974a74da7186668b915ba73764ccac 100644
--- a/ash/laser/laser_pointer_controller.h
+++ b/ash/laser/laser_pointer_controller.h
@@ -54,6 +54,9 @@ class ASH_EXPORT LaserPointerController : public ui::EventHandler,
   // allows the trail to fade away when the mouse is stationary.
   void AddStationaryPoint();
 
+  // Destroys |laser_pointer_view_|, if it exists.
+  void DestroyLaserPointerView();
+
   // Timer which will add a new stationary point when the mouse stops moving.
   // This will remove points that are too old.
   std::unique_ptr<base::Timer> stationary_timer_;
@@ -61,6 +64,12 @@ class ASH_EXPORT LaserPointerController : public ui::EventHandler,
 
   bool enabled_ = false;
 
+  // |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;
+
   // The last seen mouse location in screen coordinates.
   gfx::Point current_mouse_location_;