Get rid of {Run,Terminate}MainApplication(), and more ApplicationDelegate conversion.

mojo/environment/scoped_chromium_init.h

+// Copyright 2016 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_ENVIRONMENT_SCOPED_CHROMIUM_INIT_H_
+#define MOJO_ENVIRONMENT_SCOPED_CHROMIUM_INIT_H_
+
+#include "base/at_exit.h"
+#include "base/macros.h"
+
+namespace mojo {
+
+// Using code from //base typically requires that a number of things be
+// initialized/present. In particular the global |base::CommandLine| singleton
+// should be initialized and an |AtExitManager| should be present.
+//
+// This class is a simple helper that does these things (and tears down the
+// |AtExitManager| on destruction). Typically, it should be used in |MojoMain()|
+// as follows:
+//
+//   MojoResult MojoMain(MojoHandle application_request) {
+//     mojo::ScopedBaseInit init;
+//     ...
+//   }
+//
+// TODO(vtl): Maybe this should be called |ScopedBaseInit|, but for now I'm
+// being consistent with everything else that refers to things that use //base
+// as "chromium".
+class ScopedChromiumInit {
+ public:
+  ScopedChromiumInit();
+  ~ScopedChromiumInit();
+
+ private:
+  base::AtExitManager at_exit_manager_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedChromiumInit);
+};
+
+}  // namespace mojo
+
+#endif  // MOJO_ENVIRONMENT_SCOPED_CHROMIUM_INIT_H_