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

content/public/common/child_process_host_delegate.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_DELEGATE_H_
-#define CONTENT_PULIC_COMMON_CHILD_PROCESS_HOST_DELEGATE_H_
+#ifndef CONTENT_PUBLIC_COMMON_CHILD_PROCESS_HOST_DELEGATE_H_
+#define CONTENT_PUBLIC_COMMON_CHILD_PROCESS_HOST_DELEGATE_H_
 #pragma once
 
 #include <string>
 
+#include "content/common/content_export.h"
 #include "ipc/ipc_channel.h"
 
 namespace content {
 
 // Interface that all users of ChildProcessHost need to provide.
 class ChildProcessHostDelegate : public IPC::Channel::Listener {
  public:
   virtual ~ChildProcessHostDelegate() {}
 
-  // Derived classes return true if it's ok to shut down the child process.
-  // Normally they would return true. The exception is if the host is in the
-  // middle of sending a request to the process, in which case the other side
-  // might think it's ok to shutdown, when really it's not.
-  virtual bool CanShutdown() = 0;
+  // Delegates return true if it's ok to shut down the child process (which is
+  // the default return value). The exception is if the host is in the middle of
+  // sending a request to the process, in which case the other side might think
+  // it's ok to shutdown, when really it's not.
+  CONTENT_EXPORT virtual bool CanShutdown();
 
   // Notifies the derived class that we told the child process to kill itself.
-  virtual void ShutdownStarted() = 0;
+  virtual void ShutdownStarted() {}
 
   // Called when the child process unexpected closes the IPC channel. Delegates
   // would normally delete the object in this case.
-  virtual void OnChildDisconnected() = 0;
+  virtual void OnChildDisconnected() {}
 };
 
 };  // namespace content
 
-#endif  // CONTENT_PULIC_COMMON_CHILD_PROCESS_HOST_DELEGATE_H_
+#endif  // CONTENT_PUBLIC_COMMON_CHILD_PROCESS_HOST_DELEGATE_H_