Use native coordinates to warp the cursor to another display.

ash/wm/coordinate_conversion.h

Index: ash/wm/coordinate_conversion.h
diff --git a/ash/wm/coordinate_conversion.h b/ash/wm/coordinate_conversion.h
index f5c1af8d20f8d3af47c570591fec53dcf239a651..539e7c036b85dcc2dd232f0c0839ca9dfc2db703 100644
--- a/ash/wm/coordinate_conversion.h
+++ b/ash/wm/coordinate_conversion.h
@@ -30,11 +30,12 @@ ASH_EXPORT aura::Window* GetRootWindowMatching(const gfx::Rect& rect);
 
 // Converts the |point| from a given |window|'s coordinates into the screen
 // coordinates.
-ASH_EXPORT void ConvertPointToScreen(aura::Window* window, gfx::Point* point);
+ASH_EXPORT void ConvertPointToScreen(const aura::Window* window,
+                                     gfx::Point* point);
 
 // Converts the |point| from the screen coordinates to a given |window|'s
 // coordinates.
-ASH_EXPORT void ConvertPointFromScreen(aura::Window* window,
+ASH_EXPORT void ConvertPointFromScreen(const aura::Window* window,
                                        gfx::Point* point_in_screen);
 
 }  // namespace wm