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

ui/views/mus/aura_init.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 UI_VIEWS_MUS_AURA_INIT_H_
 #define UI_VIEWS_MUS_AURA_INIT_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "build/build_config.h"
 #include "skia/ext/refptr.h"
 #include "ui/views/mus/mus_export.h"
 
 namespace font_service {
 class FontLoader;
 }
 
 namespace mojo {
-class ApplicationImpl;
+class Shell;
 }
 
 namespace views {
 class ViewsDelegate;
 
 // Sets up necessary state for aura when run with the viewmanager.
 // |resource_file| is the path to the apk file containing the resources.
 class VIEWS_MUS_EXPORT AuraInit {
  public:
-  AuraInit(mojo::ApplicationImpl* app, const std::string& resource_file);
+  AuraInit(mojo::Shell* shell, const std::string& resource_file);
   ~AuraInit();
 
  private:
-  void InitializeResources(mojo::ApplicationImpl* app);
+  void InitializeResources(mojo::Shell* shell);
 
 #if defined(OS_LINUX) && !defined(OS_ANDROID)
   skia::RefPtr<font_service::FontLoader> font_loader_;
 #endif
 
   const std::string resource_file_;
 
   scoped_ptr<ViewsDelegate> views_delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(AuraInit);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_MUS_AURA_INIT_H_