Factor stuff from ApplicationImpl out to a new class, ApplicationImplBase.

mojo/ui/view_provider_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 MOJO_UI_VIEW_PROVIDER_APP_H_
 #define MOJO_UI_VIEW_PROVIDER_APP_H_
 
 #include <string>
 
 #include "mojo/common/strong_binding_set.h"
 #include "mojo/public/c/system/main.h"
+#include "mojo/public/cpp/application/application_delegate.h"
 #include "mojo/public/cpp/application/application_impl.h"
 #include "mojo/public/cpp/application/service_provider_impl.h"
 #include "mojo/public/cpp/system/macros.h"
 #include "mojo/services/ui/views/interfaces/view_provider.mojom.h"
 
 namespace mojo {
 namespace ui {
 
 // Abstract implementation of a simple application that offers a ViewProvider.
 // Subclasses must provide a function to create the necessary Views.
@@ skipping 44 matching lines @@
   ApplicationImpl* app_impl_ = nullptr;
   StrongBindingSet<ViewProvider> bindings_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(ViewProviderApp);
 };
 
 }  // namespace ui
 }  // namespace mojo
 
 #endif  // MOJO_UI_VIEW_PROVIDER_APP_H_