Wire up process launch error codes.

content/public/browser/render_process_host_observer.h

 // Copyright 2013 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_RENDER_PROCESS_HOST_OBSERVER_H_
 #define CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_OBSERVER_H_
 
 #include "base/process/kill.h"
 #include "base/process/process_handle.h"
 #include "content/common/content_export.h"
@@ skipping 24 matching lines @@
   //
   // A new render process may be spawned for this RenderProcessHost, but there
   // are no guarantees (e.g. if shutdown is occurring, the HostDestroyed
   // callback will happen soon and that will be it, but if the renderer crashed
   // and the user clicks 'reload', a new render process will be spawned).
   //
   // This will cause a call to WebContentsObserver::RenderProcessGone() for the
   // active renderer process for the top-level frame; for code that needs to be
   // a WebContentsObserver anyway, consider whether that API might be a better
   // choice.
+  //
+  // If |status| is TERMINATION_STATUS_LAUNCH_FAILED then |exit_code| will
+  // contain a platform specific launch failure error code. Otherwise, it will
+  // contain the exit code for the process.
   virtual void RenderProcessExited(RenderProcessHost* host,
                                    base::TerminationStatus status,
                                    int exit_code) {}
 
   // This method is invoked when the observed RenderProcessHost itself is
   // destroyed. This is guaranteed to be the last call made to the observer, so
   // if the observer is tied to the observed RenderProcessHost, it is safe to
   // delete it.
   virtual void RenderProcessHostDestroyed(RenderProcessHost* host) {}
 
  protected:
   virtual ~RenderProcessHostObserver() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_OBSERVER_H_