xml_tools, plugin XEP-0071, XEP-0277: add method expandNewLinesToXHTML:

- \n in XHTML content should not be converted to <br /> by the frontend
    - save it directly in the Atom payload for better compatibility with other clients

src/plugins/plugin_xep_0277.py

@@ -180,6 +180,7 @@ class XEP_0277(object):
                 key = check_conflict(u'{}_xhtml'.format(elem.name))
                 data = data_elt.toXml()
                 microblog_data[key] = yield self.host.plugins["TEXT-SYNTAXES"].clean_xhtml(data)
+                microblog_data[key] = xml_tools.expandNewLinesToXHTML(microblog_data[key])
             else:
                 key = check_conflict(elem.name)
                 microblog_data[key] = unicode(elem)
@@ -368,6 +369,7 @@ class XEP_0277(object):
                                 raise failure.Failure(exceptions.DataError(_("Can't have xhtml and rich content at the same time")))
                         else:  # clean the XHTML input
                             converted = yield synt.clean_xhtml(data[attr])
+                        converted = xml_tools.expandNewLinesToXHTML(converted)
 
                         xml_content = u'<div xmlns="{ns}">{converted}</div>'.format(
                                         ns=NS_XHTML,