Aura/ash split: Remove hacks and get chrome linking without ash.

ui/aura/desktop/desktop_stacking_client.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 "ui/aura/desktop/desktop_stacking_client.h"
+
+#include "ui/aura/root_window.h"
+#include "ui/aura/window.h"
+
+namespace aura {
+
+DesktopStackingClient::DesktopStackingClient() {
+  aura::client::SetStackingClient(this);
+}
+
+DesktopStackingClient::~DesktopStackingClient() {
+  aura::client::SetStackingClient(NULL);
+}
+
+Window* DesktopStackingClient::GetDefaultParent(Window* window) {
+  return window->GetRootWindow();
+}
+
+}  // namespace aura