Refactor and push window properties up to class properties.

ash/mus/shadow.cc

Index: ash/mus/shadow.cc
diff --git a/ash/mus/shadow.cc b/ash/mus/shadow.cc
index 0f9cacb543f6d81387761f46a41b73b59ddac4e3..df73ff73cecea2516d16737b299979c129109839 100644
--- a/ash/mus/shadow.cc
+++ b/ash/mus/shadow.cc
@@ -6,19 +6,19 @@
 
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/aura/window.h"
-#include "ui/aura/window_property.h"
+#include "ui/base/class_property.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/resources/grit/ui_resources.h"
 
-DECLARE_WINDOW_PROPERTY_TYPE(ash::mus::Shadow*);
+DECLARE_CLASS_PROPERTY_TYPE(ash::mus::Shadow*);
 
 namespace ash {
 namespace mus {
 namespace {
 
-DEFINE_WINDOW_PROPERTY_KEY(Shadow*, kShadowProperty, nullptr);
+DEFINE_CLASS_PROPERTY_KEY(Shadow*, kShadowProperty, nullptr);
 
 // The opacity used for active shadow when animating between
 // inactive/active shadow.