Convert UtilityProcessHost to bootstrap Mojo Channel using the Shell connection

content/public/browser/shell_context.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 CONTENT_PUBLIC_BROWSER_SHELL_CONTEXT_H_
+#define CONTENT_PUBLIC_BROWSER_SHELL_CONTEXT_H_
+
+#include <memory>
+
+#include "content/common/content_export.h"
+
+namespace shell {
+class Connector;
+}
+
+namespace content {
+
+// Sets up the Shell for the browser process. If the browser process is launched
+// from an external Shell, this configures that connection. If it was not, this
+// creates a Shell instance.
+class CONTENT_EXPORT ShellContext {
+ public:
+  virtual ~ShellContext() {}
+
+  // Create an instance of the context, binding to the external shell that
+  // launched this process or creating one. Must be called on the main thread.
+  static std::unique_ptr<ShellContext> Create();
+
+  // Returns a shell::Connector that can only be used on the IO thread. Can only
+  // be called after Create() has been called on the main thread.
+  static shell::Connector* GetConnectorForIOThread();
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_SHELL_CONTEXT_H_