Move Mojo channel initialization closer to IPC::Channel setup

content/child/mojo/mojo_application.h

+// 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.
+
+#ifndef CONTENT_CHILD_MOJO_MOJO_APPLICATION_H_
+#define CONTENT_CHILD_MOJO_MOJO_APPLICATION_H_
+
+#include "ipc/ipc_platform_file.h"
+#include "mojo/common/channel_init.h"
+#include "mojo/public/cpp/bindings/remote_ptr.h"
+#include "mojo/public/interfaces/shell/shell.mojom.h"
+
+namespace IPC {
+class Message;
+}
+
+namespace content {
+
+// MojoApplication represents the code needed to setup a child process as a
+// Mojo application via Chrome IPC. Instantiate MojoApplication and call its
+// OnMessageReceived method to give it a shot at handling Chrome IPC messages.
+// It makes the mojo::Shell interface available and calls methods on the given
+// mojo::ShellClient interface as calls come in.
+class MojoApplication {
+ public:
+  // The ShellClient pointer must remain valid for the lifetime of the
+  // MojoApplication instance.
+  explicit MojoApplication(mojo::ShellClient* shell_client);
+  ~MojoApplication();
+
+  bool OnMessageReceived(const IPC::Message& msg);
+
+  mojo::Shell* shell() { return shell_.get(); }
+
+ private:
+  void OnActivate(const IPC::PlatformFileForTransit& file);
+
+  mojo::common::ChannelInit channel_init_;
+  mojo::RemotePtr<mojo::Shell> shell_;
+  mojo::ShellClient* shell_client_;
+
+  DISALLOW_COPY_AND_ASSIGN(MojoApplication);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_CHILD_MOJO_MOJO_APPLICATION_H_