Fixing problems with constrained windows (i.e. print preview)

ash/ash_constants.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 ASH_ASH_CONSTANTS_H_
+#define ASH_ASH_CONSTANTS_H_
+
+#include "ash/ash_export.h"
+#include "ui/aura/window.h"
+#include "ui/base/ui_base_types.h"
+
+namespace ash {
+
+// The window is a constrained window and lives therefore entirely within
+// another aura window.
+ASH_EXPORT extern const aura::WindowProperty<bool>* const
+    kConstrainedWindowKey;
+
+} // namespace ash
+
+#endif  // ASH_ASH_CONSTANTS_H_