Support app window draggable areas in mash.

ash/mus/property_util.cc

 // Copyright 2015 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.
 
 #include "ash/mus/property_util.h"
 
 #include <stdint.h>
 
 #include "ash/mus/shadow.h"
 #include "components/mus/public/cpp/property_type_converters.h"
@@ skipping 217 matching lines @@
       ::mus::mojom::WindowManager::kAlwaysOnTop_Property, value);
 }
 
 bool IsAlwaysOnTop(::mus::Window* window) {
   return window->HasSharedProperty(
              ::mus::mojom::WindowManager::kAlwaysOnTop_Property) &&
          window->GetSharedProperty<bool>(
              ::mus::mojom::WindowManager::kAlwaysOnTop_Property);
 }
 
+bool ShouldRemoveStandardFrame(::mus::Window* window) {
+  return window->HasSharedProperty(
+             ::mus::mojom::WindowManager::kRemoveStandardFrame_Property) &&
+         window->GetSharedProperty<bool>(
+             ::mus::mojom::WindowManager::kRemoveStandardFrame_Property);
+}
+
 }  // namespace mus
 }  // namespace ash