Update window_parenting_utils to use aura::window

ash/common/wm/panels/panel_layout_manager.cc

 // 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.
 
 #include "ash/common/wm/panels/panel_layout_manager.h"
 
 #include <algorithm>
 #include <map>
 #include <utility>
 
@@ skipping 330 matching lines @@
   if (in_add_window_)
     return;
   base::AutoReset<bool> auto_reset_in_add_window(&in_add_window_, true);
   if (!child->aura_window()->GetProperty(kPanelAttachedKey)) {
     // This should only happen when a window is added to panel container as a
     // result of bounds change from within the application during a drag.
     // If so we have already stopped the drag and should reparent the panel
     // back to appropriate container and ignore it.
     // TODO(varkha): Updating bounds during a drag can cause problems and a more
     // general solution is needed. See http://crbug.com/251813 .
-    WmWindow* old_parent = child->GetParent();
+    aura::Window* old_parent = child->aura_window()->parent();
     child->SetParentUsingContext(child,
                                  child->GetRootWindow()->GetBoundsInScreen());
-    wm::ReparentTransientChildrenOfChild(child, old_parent, child->GetParent());
+    wm::ReparentTransientChildrenOfChild(child->aura_window(), old_parent,
+                                         child->aura_window()->parent());
     DCHECK(child->GetParent()->GetShellWindowId() !=
            kShellWindowId_PanelContainer);
     return;
   }
   PanelInfo panel_info;
   panel_info.window = child;
   panel_info.callout_widget = new PanelCalloutWidget(panel_container_);
   panel_info.slide_in = child != dragged_panel_;
   panel_windows_.push_back(panel_info);
   child->aura_window()->AddObserver(this);
@@ skipping 560 matching lines @@
     }
   }
   // This bounds change will have caused a change to the Shelf which does not
   // propogate automatically to this class, so manually recalculate bounds.
   OnWindowResized();
 }
 
 void PanelLayoutManager::OnKeyboardClosed() {}
 
 }  // namespace ash