Crm 15672

WordPress users are reporting that the CiviContribute widget fails to render when they paste it into a post or page. This PR is a short-term fix for the most common use case.

Jira issue here:
https://issues.civicrm.org/jira/browse/CRM-15672

Forum topic here:
http://forum.civicrm.org/index.php/topic,33965.0.html