Propagates window type properties during aura-mus window creation

ui/aura/client/aura_constants.h

Index: ui/aura/client/aura_constants.h
diff --git a/ui/aura/client/aura_constants.h b/ui/aura/client/aura_constants.h
index 167a77952caab0e686c61db365aa29fca44a2a72..9eb52910c9ac71afdd55ddaeb746a43bcc19e987 100644
--- a/ui/aura/client/aura_constants.h
+++ b/ui/aura/client/aura_constants.h
@@ -15,6 +15,9 @@
 
 namespace ui {
 class InputMethod;
+namespace mojom {
+enum class WindowType;
+}
 }
 
 namespace aura {
@@ -101,6 +104,9 @@ AURA_EXPORT extern const aura::WindowProperty<SkColor>* const kTopViewColor;
 // A property key to store the window icon, typically 16x16 for title bars.
 AURA_EXPORT extern const WindowProperty<gfx::ImageSkia*>* const kWindowIconKey;
 
+AURA_EXPORT extern const aura::WindowProperty<ui::mojom::WindowType>* const
+    kWindowTypeKey;
+
 // Alphabetical sort.
 
 }  // namespace client