fix spinach

app/helpers/appearances_helper.rb

 module AppearancesHelper
   def brand_title
-    if brand_item
+    if brand_item && brand_item.title
       brand_item.title
     else
       'GitLab Enterprise Edition'

app/views/layouts/_head.html.haml

 %head{prefix: "og: http://ogp.me/ns#"}
   %meta{charset: "utf-8"}
   %meta{'http-equiv' => 'X-UA-Compatible', content: 'IE=edge'}
-  %meta{content: "GitLab Enterprise Edition", name: "description"}
   %meta{name: 'referrer', content: 'origin-when-cross-origin'}
+  %meta{name: "description", content: page_description}
   -# Open Graph - http://ogp.me/
   %meta{property: 'og:type',        content: "object"}