ui_test_core: force content type as text/plain in MailHost_reportMessageList

Otherwise this is interpreted as text/html after sending html emails

bt5/erp5_ui_test_core/SkinTemplateItem/portal_skins/erp5_ui_test_core/MailHost_reportMessageList.py

@@ -17,4 +17,13 @@ for mail in message_list:
   print ""
 
 print "Total messages: %s" %len(message_list)
+
+# If messages "looks like html", zope will set content type to text/html,
+# and the assertTextPresent from selenium will be applied after the emails
+# are interpreted as html.
+# For example, the email  "Name <email@example.com>" would be interpreted as
+# an html entity and we cannot use assertTextPresent on it.
+# To prevent that, we force content type to text.
+container.REQUEST.RESPONSE.setHeader('Content-Type', 'text/plain;charset=utf-8')
+
 return printed