mash: Migrate Shelf aura::Window uses to WmWindow.

ash/aura/wm_shelf_aura.cc

Index: ash/aura/wm_shelf_aura.cc
diff --git a/ash/aura/wm_shelf_aura.cc b/ash/aura/wm_shelf_aura.cc
index 59bda6847cad01bdad03090881b33f05e3f4f777..cfeb53d1c41f2f669df5010d6532d576914d4af4 100644
--- a/ash/aura/wm_shelf_aura.cc
+++ b/ash/aura/wm_shelf_aura.cc
@@ -163,12 +163,11 @@ gfx::Rect WmShelfAura::GetUserWorkAreaBounds() const {
 }
 
 void WmShelfAura::UpdateIconPositionForWindow(WmWindow* window) {
-  shelf_->UpdateIconPositionForWindow(WmWindowAura::GetAuraWindow(window));
+  shelf_->UpdateIconPositionForWindow(window);
 }
 
 gfx::Rect WmShelfAura::GetScreenBoundsOfItemIconForWindow(WmWindow* window) {
-  return shelf_->GetScreenBoundsOfItemIconForWindow(
-      WmWindowAura::GetAuraWindow(window));
+  return shelf_->GetScreenBoundsOfItemIconForWindow(window);
 }
 
 bool WmShelfAura::ProcessGestureEvent(const ui::GestureEvent& event) {