mojo: first take on removing mojo_main_{chromium,standalone}.

mojo/public/cpp/application/lib/mojo_main_chromium.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 "base/at_exit.h"
-#include "base/command_line.h"
-#include "base/message_loop/message_loop.h"
-#include "mojo/public/cpp/application/application_delegate.h"
-#include "mojo/public/cpp/application/application_impl.h"
-
-extern "C" APPLICATION_EXPORT MojoResult CDECL MojoMain(
-    MojoHandle shell_handle) {
-  base::CommandLine::Init(0, NULL);
-#if !defined(COMPONENT_BUILD)
-  base::AtExitManager at_exit;
-#endif
-  scoped_ptr<mojo::ApplicationDelegate> delegate;
-  {
-    // We have to shut down the MessageLoop before destroying the
-    // ApplicationDelegate.
-    base::MessageLoop loop;
-    delegate.reset(mojo::ApplicationDelegate::Create());
-    mojo::ApplicationImpl app(delegate.get());
-    app.BindShell(shell_handle);
-    loop.Run();
-  }
-
-  return MOJO_RESULT_OK;
-}