Prior to commit c6d9cea, newlines were escaped as backlash-n in both text and xml output of node attribute values by crm_attribute and attrd_updater. After that commit, they were converted to spaces. However, the openstack-info agent had some bugs that relied on the previous behavior.
The ideal behavior would be to keep the newlines in text output, and convert them to entity references in XML output. However for backward compatibility with openstack-info, the text output must continue to use backslash-n for now.