Extract shell methods from ApplicationImpl into a base class, and pass this to Initialize() instead.

mash/wm/non_client_frame_controller.h

 // 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 MASH_WM_NON_CLIENT_FRAME_CONTROLLER_H_
 #define MASH_WM_NON_CLIENT_FRAME_CONTROLLER_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
 #include "base/strings/string16.h"
 #include "components/mus/public/cpp/window_observer.h"
 #include "ui/views/widget/widget_delegate.h"
 
 namespace gfx {
 class Insets;
 }
 
 namespace mojo {
-namespace shell {
-namespace mojom {
 class Shell;
 }
-}
-}
 
 namespace mus {
 class Window;
 class WindowManagerClient;
 }
 
 namespace mash {
 namespace wm {
 
 // Provides the non-client frame for mus Windows.
 class NonClientFrameController : public views::WidgetDelegateView,
                                  public mus::WindowObserver {
  public:
   // NonClientFrameController deletes itself when |window| is destroyed.
-  NonClientFrameController(mojo::shell::mojom::Shell* shell,
+  NonClientFrameController(mojo::Shell* shell,
                            mus::Window* window,
                            mus::WindowManagerClient* window_manager_client);
 
   // Returns the preferred client area insets.
   static gfx::Insets GetPreferredClientAreaInsets();
 
   // Returns the width needed to display the standard set of buttons on the
   // title bar.
   static int GetMaxTitleBarButtonWidth();
 
@@ skipping 24 matching lines @@
   // is null.
   mus::Window* window_;
 
   DISALLOW_COPY_AND_ASSIGN(NonClientFrameController);
 };
 
 }  // namespace wm
 }  // namespace mash
 
 #endif  // MASH_WM_NON_CLIENT_FRAME_CONTROLLER_H_