Bug 974127 - nsContentUtils::IsUserFocusIgnored can loop infinitely, r=ehsan

--HG--
extra : rebase_source : 303c25586b6ff1c326241d9aa192fc8235359083

content/base/src/nsContentUtils.cpp

@@ -5842,9 +5842,7 @@ nsContentUtils::IsUserFocusIgnored(nsINode* aNode)
       return true;
     }
     nsPIDOMWindow* win = aNode->OwnerDoc()->GetWindow();
-    if (win) {
-      aNode = win->GetFrameElementInternal();
-    }
+    aNode = win ? win->GetFrameElementInternal() : nullptr;
   }
 
   return false;