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

content/browser/utility_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_BROWSER_UTILITY_PROCESS_HOST_H_
 #define CONTENT_BROWSER_UTILITY_PROCESS_HOST_H_
 #pragma once
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/process_util.h"
-#include "content/browser/browser_child_process_host.h"
 #include "content/common/content_export.h"
+#include "content/public/browser/browser_child_process_host_delegate.h"
 #include "content/public/browser/browser_thread.h"
+#include "ipc/ipc_message.h"
+
+class BrowserChildProcessHost;
 
 // This class acts as the browser-side host to a utility child process.  A
 // utility process is a short-lived sandboxed process that is created to run
 // a specific task.  This class lives solely on the IO thread.
 // If you need a single method call in the sandbox, use StartFooBar(p).
 // If you need multiple batches of work to be done in the sandboxed process,
 // use StartBatchMode(), then multiple calls to StartFooBar(p),
 // then finish with EndBatchMode().
-class CONTENT_EXPORT UtilityProcessHost : public BrowserChildProcessHost {
+class CONTENT_EXPORT UtilityProcessHost
+    : public content::BrowserChildProcessHostDelegate,
+      public IPC::Message::Sender {
  public:
   // An interface to be implemented by consumers of the utility process to
   // get results back.  All functions are called on the thread passed along
   // to UtilityProcessHost.
   class CONTENT_EXPORT Client : public base::RefCountedThreadSafe<Client> {
    public:
     Client();
 
     // Called when the process has crashed.
     virtual void OnProcessCrashed(int exit_code);
 
     // Allow the client to filter IPC messages.
     virtual bool OnMessageReceived(const IPC::Message& message);
 
    protected:
     friend class base::RefCountedThreadSafe<Client>;
 
     virtual ~Client();
 
    private:
     friend class UtilityProcessHost;
 
     DISALLOW_COPY_AND_ASSIGN(Client);
   };
 
   UtilityProcessHost(Client* client,
                      content::BrowserThread::ID client_thread_id);
   virtual ~UtilityProcessHost();
 
-  // BrowserChildProcessHost override
+  // IPC::Message::Sender implementation:
   virtual bool Send(IPC::Message* message) OVERRIDE;
 
   // Starts utility process in batch mode. Caller must call EndBatchMode()
   // to finish the utility process.
   bool StartBatchMode();
 
   // Ends the utility process. Must be called after StartBatchMode().
   void EndBatchMode();
 
   void set_exposed_dir(const FilePath& dir) { exposed_dir_ = dir; }
   void set_no_sandbox(bool flag) { no_sandbox_ = flag; }
   void set_child_flags(int flags) { child_flags_ = flags; }
   void set_use_linux_zygote(bool flag) { use_linux_zygote_ = flag; }
 #if defined(OS_POSIX)
   void set_env(const base::environment_vector& env) { env_ = env; }
 #endif
 
  protected:
   // Allow these methods to be overridden for tests.
   virtual FilePath GetUtilityProcessCmd();
 
  private:
   // Starts a process if necessary.  Returns true if it succeeded or a process
   // has already been started via StartBatchMode().
   bool StartProcess();
 
-  // IPC messages:
+  // BrowserChildProcessHost:
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
-
-  // BrowserChildProcessHost:
   virtual void OnProcessCrashed(int exit_code) OVERRIDE;
 
   // A pointer to our client interface, who will be informed of progress.
   scoped_refptr<Client> client_;
   content::BrowserThread::ID client_thread_id_;
   // True when running in batch mode, i.e., StartBatchMode() has been called
   // and the utility process will run until EndBatchMode().
   bool is_batch_mode_;
 
   // Allows a directory to be opened through the sandbox, in case it's needed by
   // the operation.
   FilePath exposed_dir_;
 
   // Whether to pass switches::kNoSandbox to the child.
   bool no_sandbox_;
 
   // Flags defined in ChildProcessHost with which to start the process.
   int child_flags_;
 
   // If the |no_sandbox_| flag is off, and we are on Linux, launch the
   // utility process from the zygote. Defaults to false.
   // Can only be used for tasks that do not require FS access.
   bool use_linux_zygote_;
 
   base::environment_vector env_;
 
   bool started_;
 
+  scoped_ptr<BrowserChildProcessHost> process_;
+
   DISALLOW_COPY_AND_ASSIGN(UtilityProcessHost);
 };
 
 #endif  // CONTENT_BROWSER_UTILITY_PROCESS_HOST_H_