aura: Add X11 host window management.

ui/aura/hostwm/host_window_delegate.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/hostwm/host_window_delegate.h"
+
+#include "ui/aura/window.h"
+#include "ui/aura/window_property.h"
+
+DECLARE_WINDOW_PROPERTY_TYPE(aura::HostWindowDelegate*)
+
+namespace aura {
+
+DEFINE_LOCAL_WINDOW_PROPERTY_KEY(
+    HostWindowDelegate*, kHostWindowDelegateKey, NULL);
+
+void SetHostWindowDelegate(Window* window, HostWindowDelegate* delegate) {
+  window->SetProperty(kHostWindowDelegateKey, delegate);
+}
+
+HostWindowDelegate* GetHostWindowDelegate(Window* window) {
+  return window->GetProperty(kHostWindowDelegateKey);
+}
+
+}  // namespace aura