Make ApplicationTestBase not use ApplicationImpl.

mojo/services/files/c/tests/mojio_impl_test_base.cc

 // 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.
 
 #include "files/c/tests/mojio_impl_test_base.h"
 
 #include "files/interfaces/files.mojom-sync.h"
 #include "files/interfaces/files.mojom.h"
-#include "mojo/public/cpp/application/application_impl.h"
 #include "mojo/public/cpp/application/connect.h"
 #include "mojo/public/cpp/bindings/interface_request.h"
 #include "mojo/public/cpp/bindings/synchronous_interface_ptr.h"
 #include "mojo/public/cpp/environment/logging.h"
 
 using mojo::SynchronousInterfacePtr;
 
 namespace mojio {
 namespace test {
 
 MojioImplTestBase::MojioImplTestBase() {
 }
 
 MojioImplTestBase::~MojioImplTestBase() {
 }
 
 void MojioImplTestBase::SetUp() {
   mojo::test::ApplicationTestBase::SetUp();
 
   SynchronousInterfacePtr<mojo::files::Files> files;
-  mojo::ConnectToService(application_impl()->shell(), "mojo:files",
-                         GetSynchronousProxy(&files));
+  mojo::ConnectToService(shell(), "mojo:files", GetSynchronousProxy(&files));
 
   mojo::files::Error error = mojo::files::Error::INTERNAL;
   MOJO_CHECK(
       files->OpenFileSystem(nullptr, mojo::GetProxy(&directory_), &error));
   MOJO_CHECK(error == mojo::files::Error::OK);
 }
 
 }  // namespace test
 }  // namespace mojio