Refactor PhantomWindowController so that the PhantomWindowController owns the phantom window

ash/wm/caption_buttons/alternate_frame_size_button.h

 // Copyright 2013 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_CAPTION_BUTTONS_ALTERNATE_FRAME_SIZE_BUTTON_H_
 #define ASH_WM_CAPTION_BUTTONS_ALTERNATE_FRAME_SIZE_BUTTON_H_
 
 #include "ash/ash_export.h"
 #include "ash/wm/caption_buttons/alternate_frame_size_button_delegate.h"
 #include "ash/wm/caption_buttons/frame_caption_button.h"
 #include "ash/wm/workspace/snap_types.h"
 #include "base/timer/timer.h"
 
 namespace views {
 class Widget;
 }
 
 namespace ash {
 class AlternateFrameSizeButtonDelegate;
 
+namespace internal {
+class PhantomWindowController;
+}
+
 // The maximize/restore button when using the alternate button style.
 // When the mouse is pressed over the size button or the size button is touched:
 // - The minimize and close buttons are set to snap left and snap right
 //   respectively.
 // - The pressed button is updated during the drag to reflect the button
 //   underneath the mouse cursor. (The size button is potentially unpressed).
 // When the drag terminates, the action for the pressed button is executed.
 // For the sake of simplicity, the size button is the event handler for a click
 // starting on the size button and the entire drag (including when the size
 // button is unpressed).
@@ skipping 54 matching lines @@
   base::OneShotTimer<AlternateFrameSizeButton> set_buttons_to_snap_mode_timer_;
 
   // Whether the buttons adjacent to the size button snap the window left and
   // right.
   bool in_snap_mode_;
 
   // The action of the currently pressed button. If |snap_type_| == SNAP_NONE,
   // the size button's default action is run when clicked.
   SnapType snap_type_;
 
+  // Displays a preview of how the window's bounds will change as a result of
+  // snapping the window left or right. The preview is only visible if the snap
+  // left or snap right button is pressed.
+  scoped_ptr<internal::PhantomWindowController> phantom_window_controller_;
+
   DISALLOW_COPY_AND_ASSIGN(AlternateFrameSizeButton);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_CAPTION_BUTTONS_ALTERNATE_FRAME_SIZE_BUTTON_H_