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

mandoline/ui/omnibox/omnibox_application.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 MANDOLINE_UI_OMNIBOX_OMNIBOX_APPLICATION_H_
 #define MANDOLINE_UI_OMNIBOX_OMNIBOX_APPLICATION_H_
 
 #include "base/macros.h"
 #include "mandoline/ui/desktop_ui/public/interfaces/omnibox.mojom.h"
 #include "mojo/services/tracing/public/cpp/tracing_impl.h"
 #include "mojo/shell/public/cpp/application_delegate.h"
 #include "mojo/shell/public/cpp/interface_factory.h"
 
 namespace mojo {
-class ApplicationImpl;
+class Shell;
 }
 
 namespace mandoline {
 
 class OmniboxApplication : public mojo::ApplicationDelegate,
                            public mojo::InterfaceFactory<Omnibox> {
  public:
   OmniboxApplication();
   ~OmniboxApplication() override;
 
  private:
   // Overridden from mojo::ApplicationDelegate:
-  void Initialize(mojo::ApplicationImpl* app) override;
+  void Initialize(mojo::Shell* shell, const std::string& url,
+                  uint32_t id) override;
   bool AcceptConnection(
       mojo::ApplicationConnection* connection) override;
 
   // Overridden from mojo::InterfaceFactory<Omnibox>:
   void Create(mojo::ApplicationConnection* connection,
               mojo::InterfaceRequest<Omnibox> request) override;
 
-  mojo::ApplicationImpl* app_;
+  mojo::Shell* shell_;
   mojo::TracingImpl tracing_;
 
   DISALLOW_COPY_AND_ASSIGN(OmniboxApplication);
 };
 
 }  // namespace mandoline
 
 #endif  // MANDOLINE_UI_OMNIBOX_OMNIBOX_APPLICATION_H_