Revert of Moving coordinate conversion methods from ash/wm to ui/wm.

ui/wm/core/coordinate_conversion.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 UI_WM_CORE_COORDINATE_CONVERSION_H_
-#define UI_WM_CORE_COORDINATE_CONVERSION_H_
-
-#include "ui/wm/wm_export.h"
-
-namespace aura {
-class Window;
-}  // namespace aura
-
-namespace gfx {
-class Point;
-}  // namespace gfx
-
-namespace wm {
-
-// Converts the |point| from a given |window|'s coordinates into the screen
-// coordinates.
-WM_EXPORT void ConvertPointToScreen(const aura::Window* window,
-                                    gfx::Point* point);
-
-// Converts the |point| from the screen coordinates to a given |window|'s
-// coordinates.
-WM_EXPORT void ConvertPointFromScreen(const aura::Window* window,
-                                      gfx::Point* point_in_screen);
-
-}  // namespace wm
-
-#endif  // UI_WM_CORE_COORDINATE_CONVERSION_H_