Makes ash/mus use RootWindowControllerCommon

ash/mus/background_layout.h

Index: ash/mus/background_layout.h
diff --git a/ash/mus/background_layout.h b/ash/mus/background_layout.h
deleted file mode 100644
index 3e9b86bb9014dc068525fcfecb6ac751c33f49fe..0000000000000000000000000000000000000000
--- a/ash/mus/background_layout.h
+++ /dev/null
@@ -1,30 +0,0 @@
-// 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.
-
-#ifndef ASH_MUS_BACKGROUND_LAYOUT_H_
-#define ASH_MUS_BACKGROUND_LAYOUT_H_
-
-#include "ash/mus/layout_manager.h"
-#include "base/macros.h"
-
-namespace ash {
-namespace mus {
-
-// Lays out the desktop background within background containers.
-class BackgroundLayout : public LayoutManager {
- public:
-  explicit BackgroundLayout(::mus::Window* owner);
-  ~BackgroundLayout() override;
-
- private:
-  // Overridden from LayoutManager:
-  void LayoutWindow(::mus::Window* window) override;
-
-  DISALLOW_COPY_AND_ASSIGN(BackgroundLayout);
-};
-
-}  // namespace mus
-}  // namespace ash
-
-#endif  // ASH_MUS_BACKGROUND_LAYOUT_H_