[css-flexbox] Update DoC

Author: fantasai

css-flexbox/issues-lc-20150514.txt

@@ -200,7 +200,7 @@ From:     John Waterson
 Comment:  https://lists.w3.org/Archives/Public/www-style/2015Oct/0115.html
 Response: https://lists.w3.org/Archives/Public/www-style/2015Oct/0116.html
 Response: https://lists.w3.org/Archives/Public/www-style/2015Dec/0024.html
-Open:     OutOfScope
+Closed:   OutOfScope
 ----
 Issue 26.
 Summary:  Percentages resolving against definite max-height