tools (xml_tools): keeps data form result headers sorted

src/tools/xml_tools.py

@@ -27,6 +27,7 @@ from wokkel import data_form
 from twisted.words.xish import domish
 from twisted.words.protocols.jabber import jid
 from sat.core import exceptions
+from collections import OrderedDict
 
 
 """This library help manage XML used in SàT (parameters, registration, etc)"""
@@ -141,7 +142,7 @@ def dataFormResult2AdvancedList(xmlui, form_xml):
     @param form_xml (domish.Element): element of the data form
     @return: the completed XMLUI instance
     """
-    headers = {}
+    headers = OrderedDict()
     try:
         reported_elt = form_xml.elements('jabber:x:data', 'reported').next()
     except StopIteration: