Remove Client relationship between mojo.Shell/mojo.Application

mojo/public/cpp/application/lib/application_test_main.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 "mojo/public/c/system/main.h"
 #include "mojo/public/cpp/application/application_test_base.h"
 #include "mojo/public/cpp/environment/environment.h"
-#include "mojo/public/interfaces/application/shell.mojom.h"
 
-MojoResult MojoMain(MojoHandle shell_handle) {
+MojoResult MojoMain(MojoHandle handle) {
   // An Environment instance is needed to construct run loops.
   mojo::Environment environment;
 
-  mojo::ShellPtr shell;
-  shell.Bind(MakeScopedHandle(mojo::MessagePipeHandle(shell_handle)));
-  return mojo::test::RunAllTests(shell.Pass());
+  return mojo::test::RunAllTests(handle);
 }