Make PlatformViewport and NativeViewportImpl use Shell* instead of ApplicationImpl*.

shell/android/native_viewport_application_loader.cc

 // Copyright 2014 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.
 
 #include "shell/android/native_viewport_application_loader.h"
 
 #include "mojo/public/cpp/application/application_impl.h"
 #include "services/gles2/gpu_state.h"
 #include "services/native_viewport/native_viewport_impl.h"
 
@@ skipping 15 matching lines @@
   app_.reset(new mojo::ApplicationImpl(this, application_request.Pass()));
 }
 
 bool NativeViewportApplicationLoader::ConfigureIncomingConnection(
     mojo::ServiceProviderImpl* service_provider_impl) {
   service_provider_impl->AddService<mojo::NativeViewport>(
       [this](const ConnectionContext& connection_context,
              InterfaceRequest<mojo::NativeViewport> native_viewport_request) {
         if (!gpu_state_)
           gpu_state_ = new gles2::GpuState();
-        new native_viewport::NativeViewportImpl(app_.get(), false, gpu_state_,
-                                                native_viewport_request.Pass());
+        new native_viewport::NativeViewportImpl(
+            app_->shell(), false, gpu_state_, native_viewport_request.Pass());
       });
   service_provider_impl->AddService<mojo::Gpu>(
       [this](const ConnectionContext& connection_context,
              InterfaceRequest<mojo::Gpu> gpu_request) {
         if (!gpu_state_)
           gpu_state_ = new gles2::GpuState();
         new gles2::GpuImpl(gpu_request.Pass(), gpu_state_);
       });
   return true;
 }
 
 }  // namespace shell