Add a Content API around BrowserChildProcessHost, similar to what was done with ChildProcessHost....

content/public/common/child_process_host.h

 // Copyright (c) 2011 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_PULIC_COMMON_CHILD_PROCESS_HOST_H_
 #define CONTENT_PULIC_COMMON_CHILD_PROCESS_HOST_H_
 #pragma once
 
 #include "build/build_config.h"
 #include "content/common/content_export.h"
 #include "ipc/ipc_channel_proxy.h"
 
 class FilePath;
 
 namespace content {
 
 class ChildProcessHostDelegate;
 
-// Interface that all users of ChildProcessHost need to provide.
+// This represents a non-browser process. This can include traditional child
+// processes like plugins, or an embedder could even use this for long lived
+// processes that run independent of the browser process.
 class CONTENT_EXPORT ChildProcessHost : public IPC::Message::Sender {
  public:
   virtual ~ChildProcessHost() {}
 
   // Used to create a child process host. The delegate must outlive this object.
   static ChildProcessHost* Create(
       ChildProcessHostDelegate* delegate);
 
   // These flags may be passed to GetChildPath in order to alter its behavior,
   // causing it to return a child path more suited to a specific task.
@@ skipping 58 matching lines @@
 
 #if defined(OS_POSIX)
   // See IPC::Channel::TakeClientFileDescriptor.
   virtual int TakeClientFileDescriptor() = 0;
 #endif
 };
 
 };  // namespace content
 
 #endif  // CONTENT_PULIC_COMMON_CHILD_PROCESS_HOST_H_