Re-commit r22981 after backout at r22992

chrome/common/child_process_host.h

 // Copyright (c) 2009 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 CHROME_COMMON_CHILD_PROCESS_HOST_H_
 #define CHROME_COMMON_CHILD_PROCESS_HOST_H_
 
 #include <list>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/scoped_ptr.h"
 #include "chrome/browser/renderer_host/resource_dispatcher_host.h"
 #include "ipc/ipc_channel.h"
 
 class NotificationType;
 
 // Plugins/workers and other child processes that live on the IO thread should
 // derive from this class.
 class ChildProcessHost : public ResourceDispatcherHost::Receiver,
                          public IPC::Channel::Listener {
  public:
   virtual ~ChildProcessHost();
 
+  // Returns the pathname to be used for a child process.  If a subprocess
+  // pathname was specified on the command line, that will be used.  Otherwise,
+  // the default child process pathname will be returned.  On most platforms,
+  // this will be the same as the currently-executing process.  On failure,
+  // returns an empty wstring.
+  static std::wstring GetChildPath();
+
   // ResourceDispatcherHost::Receiver implementation:
   virtual bool Send(IPC::Message* msg);
 
   // The Iterator class allows iteration through either all child processes, or
   // ones of a specific type, depending on which constructor is used.  Note that
   // this should be done from the IO thread and that the iterator should not be
   // kept around as it may be invalidated on subsequent event processing in the
   // event loop.
   class Iterator {
    public:
@@ skipping 65 matching lines @@
   bool opening_channel_;
 
   // The IPC::Channel.
   scoped_ptr<IPC::Channel> channel_;
 
   // IPC Channel's id.
   std::string channel_id_;
 };
 
 #endif  // CHROME_COMMON_CHILD_PROCESS_HOST_H_