aura: Add X11 host window management.

ui/aura/hostwm/host_window_delegate.h

+// 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.
+
+#ifndef UI_AURA_HOSTWM_HOST_WINDOW_DELEGATE_H_
+#define UI_AURA_HOSTWM_HOST_WINDOW_DELEGATE_H_
+
+#include "ui/aura/aura_export.h"
+#include "ui/gfx/rect.h"
+
+namespace aura {
+class Window;
+
+// An interface implemented by an object that configures and responds to
+// changes to a host window's state.
+class AURA_EXPORT HostWindowDelegate {
+ public:
+  // Attempt to close window. This is a no-op for host windows that can't be
+  // closed.
+  virtual void CloseWindow() = 0;
+
+  // Determines if the window can be resized.
+  virtual bool CanResize() = 0;
+
+ protected:
+  virtual ~HostWindowDelegate() {}
+};
+
+// Sets/Gets the HostWindowDelegate on the Window. No ownership changes.
+AURA_EXPORT void SetHostWindowDelegate(Window* window,
+                                       HostWindowDelegate* delegate);
+AURA_EXPORT HostWindowDelegate* GetHostWindowDelegate(Window* window);
+
+}  // namespace aura
+
+#endif  // UI_AURA_HOSTWM_HOST_WINDOW_DELEGATE_H_