bug fix: erase old cells names before uploading new content

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@3809 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Form/PDFForm.py

@@ -281,6 +281,7 @@ class PDFForm(File):
 
     file.seek(0) # file is always valid here
     values = self.pdftk.dumpDataFields(file)
+    self.cells = {}
     for v in values :
       if v["FieldType"] != "Button" :
         k = v["FieldName"]