Removes most of aura dependencies from DefaultState

ash/wm/panels/panel_window_resizer.cc

Index: ash/wm/panels/panel_window_resizer.cc
diff --git a/ash/wm/panels/panel_window_resizer.cc b/ash/wm/panels/panel_window_resizer.cc
index 501503ad7b52905b1680b95a1d6963e0c19805ca..9e294dc699d8bda7d807f340ce12b47e5f8953fe 100644
--- a/ash/wm/panels/panel_window_resizer.cc
+++ b/ash/wm/panels/panel_window_resizer.cc
@@ -11,6 +11,7 @@
 #include "ash/shelf/shelf_widget.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
+#include "ash/wm/common/window_parenting_utils.h"
 #include "ash/wm/panels/panel_layout_manager.h"
 #include "ash/wm/window_state.h"
 #include "ash/wm/window_util.h"
@@ -180,7 +181,10 @@ void PanelWindowResizer::StartedDragging() {
     aura::Window* old_parent = target->parent();
     aura::client::ParentWindowWithContext(
         target, target_root, target_root->GetBoundsInScreen());
-    wm::ReparentTransientChildrenOfChild(target, old_parent, target->parent());
+    ash::wm::ReparentTransientChildrenOfChild(
+        ash::wm::WmWindowAura::Get(target),
+        ash::wm::WmWindowAura::Get(old_parent),
+        ash::wm::WmWindowAura::Get(target->parent()));
   }
 }
 
@@ -196,7 +200,10 @@ void PanelWindowResizer::FinishDragging() {
     aura::Window* old_parent = target->parent();
     aura::client::ParentWindowWithContext(
         target, target_root, gfx::Rect(last_location_, gfx::Size()));
-    wm::ReparentTransientChildrenOfChild(target, old_parent, target->parent());
+    ash::wm::ReparentTransientChildrenOfChild(
+        ash::wm::WmWindowAura::Get(target),
+        ash::wm::WmWindowAura::Get(old_parent),
+        ash::wm::WmWindowAura::Get(target->parent()));
   }
 
   // If we started the drag in one root window and moved into another root