Refactor and push window properties up to class properties.

ui/aura/window_port.h

 // Copyright 2016 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_WINDOW_PORT_H_
 #define UI_AURA_WINDOW_PORT_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <string>
 
 #include "base/observer_list.h"
 #include "base/strings/string16.h"
 #include "ui/aura/aura_export.h"
+#include "ui/base/class_property.h"
 
 namespace gfx {
 class Rect;
 }
 
 namespace aura {
 
 class Window;
 class WindowObserver;
 
-// See comments in OnWillChangeProperty() for details.
-struct AURA_EXPORT WindowPortPropertyData {
-  virtual ~WindowPortPropertyData() {}
-};
-
 // WindowPort defines an interface to enable Window to be used with or without
 // mus. WindowPort is owned by Window and called at key points in Windows
 // lifetime that enable Window to be used in both environments.
 //
 // If a Window is created without an explicit WindowPort then
 // Env::CreateWindowPort() is used to create the WindowPort.
 class AURA_EXPORT WindowPort {
  public:
   virtual ~WindowPort() {}
 
@@ skipping 17 matching lines @@
   virtual void OnWillMoveChild(size_t current_index, size_t dest_index) = 0;
 
   virtual void OnVisibilityChanged(bool visible) = 0;
 
   virtual void OnDidChangeBounds(const gfx::Rect& old_bounds,
                                  const gfx::Rect& new_bounds) = 0;
 
   // Called before a property is changed. The return value from this is supplied
   // into OnPropertyChanged() so that WindowPort may pass data between the two
   // calls.
-  virtual std::unique_ptr<WindowPortPropertyData> OnWillChangeProperty(
+  virtual std::unique_ptr<ui::PropertyData> OnWillChangeProperty(
       const void* key) = 0;
 
   // Called after a property changes, but before observers are notified. |data|
   // is the return value from OnWillChangeProperty().
   virtual void OnPropertyChanged(
       const void* key,
-      std::unique_ptr<WindowPortPropertyData> data) = 0;
+      std::unique_ptr<ui::PropertyData> data) = 0;
 
  protected:
   // Returns the WindowPort associated with a Window.
   static WindowPort* Get(Window* window);
 
   // Returns the ObserverList of a Window.
   static base::ObserverList<WindowObserver, true>* GetObservers(Window* window);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_PORT_H_