Update window_parenting_utils to use aura::window

ash/common/wm/panels/panel_window_resizer.cc

Index: ash/common/wm/panels/panel_window_resizer.cc
diff --git a/ash/common/wm/panels/panel_window_resizer.cc b/ash/common/wm/panels/panel_window_resizer.cc
index e4047eb820d7317f22054b03e115e2489872cb6f..4ab5367f78f2fa45128f670455aa38935a7cf427 100644
--- a/ash/common/wm/panels/panel_window_resizer.cc
+++ b/ash/common/wm/panels/panel_window_resizer.cc
@@ -164,8 +164,9 @@ void PanelWindowResizer::StartedDragging() {
     WmWindow* old_parent = target->GetParent();
     target->SetParentUsingContext(target_root,
                                   target_root->GetBoundsInScreen());
-    wm::ReparentTransientChildrenOfChild(target, old_parent,
-                                         target->GetParent());
+    wm::ReparentTransientChildrenOfChild(target->aura_window(),
+                                         old_parent->aura_window(),
+                                         target->GetParent()->aura_window());
   }
 }
 
@@ -183,8 +184,9 @@ void PanelWindowResizer::FinishDragging() {
     WmWindow* old_parent = target->GetParent();
     target->SetParentUsingContext(target_root,
                                   gfx::Rect(last_location_, gfx::Size()));
-    wm::ReparentTransientChildrenOfChild(target, old_parent,
-                                         target->GetParent());
+    wm::ReparentTransientChildrenOfChild(target->aura_window(),
+                                         old_parent->aura_window(),
+                                         target->GetParent()->aura_window());
   }
 
   // If we started the drag in one root window and moved into another root