Fix error on new_promo page.

r2/r2/templates/promotelinkbase.html

@@ -23,6 +23,7 @@
 <%!
   from r2.config import feature
   from r2.lib.media import thumbnail_url
+  from r2.lib.filters import jssafe
   from r2.lib.pages import UserText
   import simplejson
   from babel.numbers import format_currency