Wire up process launch error codes.

content/public/browser/browser_child_process_host_delegate.h

Index: content/public/browser/browser_child_process_host_delegate.h
diff --git a/content/public/browser/browser_child_process_host_delegate.h b/content/public/browser/browser_child_process_host_delegate.h
index ac59a2e553cd53435aa562e18be8eea2c3c0844e..892ca25c9f9a917e893a851356277267ebe19bad 100644
--- a/content/public/browser/browser_child_process_host_delegate.h
+++ b/content/public/browser/browser_child_process_host_delegate.h
@@ -27,8 +27,8 @@ class CONTENT_EXPORT BrowserChildProcessHostDelegate : public IPC::Listener {
   virtual void OnProcessLaunched() {}
 
   // Called if the process failed to launch.  In this case the process never
-  // started so there is no available exit code.
-  virtual void OnProcessLaunchFailed() {}
+  // started so the code here is a platform specific error code.
+  virtual void OnProcessLaunchFailed(int error_code) {}
 
   // Called if the process crashed. |exit_code| is the status returned when the
   // process crashed (for posix, as returned from waitpid(), for Windows, as