Move WindowResizer to CoreWM.

ash/wm/window_resizer_factory.h

Index: ash/wm/window_resizer_factory.h
===================================================================
--- ash/wm/window_resizer_factory.h	(revision 0)
+++ ash/wm/window_resizer_factory.h	(revision 0)
@@ -0,0 +1,36 @@
+// Copyright (c) 2012 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_WM_WINDOW_RESIZER_FACTORY_H_
+#define ASH_WM_WINDOW_RESIZER_FACTORY_H_
+
+#include "ash/ash_export.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace aura {
+class Window;
+}
+
+namespace gfx {
+class Point;
+}
+
+namespace views {
+namespace corewm {
+class WindowResizer;
+}
+}
+
+namespace ash {
+
+// Creates a WindowResizer for |window|. This can return a scoped_ptr
+// initialized with NULL if |window| should not be resized nor dragged.
+ASH_EXPORT scoped_ptr<views::corewm::WindowResizer> CreateWindowResizer(
+    aura::Window* window,
+    const gfx::Point& point_in_parent,
+    int window_component);
+
+}  // namespace ash
+
+#endif  // ASH_WM_WINDOW_RESIZER_FACTORY_H_