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

content/public/test/test_mojo_app.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 CONTENT_PUBLIC_TEST_TEST_MOJO_APP_H_
 #define CONTENT_PUBLIC_TEST_TEST_MOJO_APP_H_
 
 #include "base/macros.h"
 #include "content/public/test/test_mojo_service.mojom.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "mojo/shell/public/cpp/application_delegate.h"
 #include "mojo/shell/public/cpp/interface_factory.h"
 #include "url/gurl.h"
 
 namespace content {
 
 extern const char kTestMojoAppUrl[];
 
 // Simple Mojo app which provides a TestMojoService impl. The app terminates
 // itself after its TestService fulfills a single DoSomething call.
 class TestMojoApp : public mojo::ApplicationDelegate,
                     public mojo::InterfaceFactory<TestMojoService>,
                     public TestMojoService {
  public:
   TestMojoApp();
   ~TestMojoApp() override;
 
  private:
   // 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;
 
   // mojo::InterfaceFactory<TestMojoService>:
   void Create(mojo::ApplicationConnection* connection,
               mojo::InterfaceRequest<TestMojoService> request) override;
 
   // TestMojoService:
   void DoSomething(const DoSomethingCallback& callback) override;
   void GetRequestorURL(const GetRequestorURLCallback& callback) override;
 
   mojo::Binding<TestMojoService> service_binding_;
 
   // Not owned.
-  mojo::ApplicationImpl* app_;
+  mojo::Shell* shell_;
 
   // The URL of the app connecting to us.
   GURL requestor_url_;
 
   DISALLOW_COPY_AND_ASSIGN(TestMojoApp);
 };
 
 }  // namespace
 
 #endif  // CONTENT_PUBLIC_TEST_TEST_MOJO_APP_H_