Convert //chrome/browser/chromeos from scoped_ptr to std::unique_ptr

chrome/browser/chromeos/first_run/drive_first_run_controller.h

Index: chrome/browser/chromeos/first_run/drive_first_run_controller.h
diff --git a/chrome/browser/chromeos/first_run/drive_first_run_controller.h b/chrome/browser/chromeos/first_run/drive_first_run_controller.h
index 128377e498f360df70f10c2d43ae9c3524145283..d7dba57fc543ccb707c024c030b91b914785bf50 100644
--- a/chrome/browser/chromeos/first_run/drive_first_run_controller.h
+++ b/chrome/browser/chromeos/first_run/drive_first_run_controller.h
@@ -77,7 +77,7 @@ class DriveFirstRunController {
   void CleanUp();
 
   Profile* profile_;
-  scoped_ptr<DriveWebContentsManager> web_contents_manager_;
+  std::unique_ptr<DriveWebContentsManager> web_contents_manager_;
   base::OneShotTimer web_contents_timer_;
   base::OneShotTimer initial_delay_timer_;
   bool started_;