[ObjC ARC] Converts ios/chrome/browser/ui/omnibox:omnibox_internal to ARC.

ios/chrome/browser/ui/omnibox/page_info_view_controller.h

Index: ios/chrome/browser/ui/omnibox/page_info_view_controller.h
diff --git a/ios/chrome/browser/ui/omnibox/page_info_view_controller.h b/ios/chrome/browser/ui/omnibox/page_info_view_controller.h
index 8965ea21233bf5886d7526f7682ab921893fa0eb..f8eb05987cd50103303e8cf3e4cc4a4e6bfec655 100644
--- a/ios/chrome/browser/ui/omnibox/page_info_view_controller.h
+++ b/ios/chrome/browser/ui/omnibox/page_info_view_controller.h
@@ -57,8 +57,7 @@ class PageInfoModelBubbleBridge : public PageInfoModelObserver {
     // If the window is animating closed when this is called, the
     // animation could be holding the last reference to |controller_|
     // (and thus |this|).  Pin it until the task is completed.
-    base::scoped_nsobject<PageInfoViewController> keep_alive(
-        [controller_ retain]);
+    base::scoped_nsobject<PageInfoViewController> keep_alive(controller_);
     [controller_ performLayout];
   }