Extract the code for supporing extended desktop from WorkspaceWindowResizer into DragWindowResizer.

ash/wm/drag_window_controller.h

 // 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_DRAG_WINDOW_CONTROLLER_H_
 #define ASH_WM_DRAG_WINDOW_CONTROLLER_H_
 
 #include "ash/ash_export.h"
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
@@ skipping 36 matching lines @@
   void Hide();
 
   // This is used to set bounds for the drag window immediately. This should
   // be called only when the drag window is already visible.
   void SetBounds(const gfx::Rect& bounds);
 
   // Sets the opacity of the drag window.
   void SetOpacity(float opacity);
 
  private:
-  FRIEND_TEST_ALL_PREFIXES(WorkspaceWindowResizerTest, DragWindowController);
+  FRIEND_TEST_ALL_PREFIXES(DragWindowResizerTest, DragWindowController);
 
   // Creates and shows the |drag_widget_| at |bounds|.
   // |layer| is shown on top of the drag window if it is non-NULL.
   // |layer| is not owned by this object.
   void CreateDragWidget(const gfx::Rect& bounds);
 
   // Sets bounds of the drag window. The window is shown on |dst_display_|
   // if its id() is valid. Otherwise, a display nearest to |bounds| is chosen.
   void SetBoundsInternal(const gfx::Rect& bounds);
 
@@ skipping 20 matching lines @@
   // the layer.
   ui::Layer* layer_;
 
   DISALLOW_COPY_AND_ASSIGN(DragWindowController);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_WM_DRAG_WINDOW_CONTROLLER_H_