[IMP] delete_unused: new option to remove the xmlids

The `delete_unused` is used we want to keep a record that no longer
define in the data if it was used.
It sometimes happen that its xmlid is reused for another record (which
may belong to another model). This new option allow to avoid errors.

closes #41

Signed-off-by: Alvaro Fuentes Suarez (afu) <afu@odoo.com>

Author: KangOl

src/util/records.py

@@ -921,6 +921,7 @@ def add_ref(ref):
 
 def delete_unused(cr, *xmlids, **kwargs):
     deactivate = kwargs.pop("deactivate", False)
+    keep_xmlids = kwargs.pop("keep_xmlids", True)
     if kwargs:
         raise TypeError("delete_unused() got an unexpected keyword argument %r" % kwargs.popitem()[0])
 
@@ -998,6 +999,19 @@ def delete_unused(cr, *xmlids, **kwargs):
             if deactivate_ids:
                 cr.execute('UPDATE "{}" SET active = false WHERE id IN %s'.format(table), [deactivate_ids])
 
+    if not keep_xmlids:
+        query = """
+            WITH xids AS (
+                {}
+            )
+            DELETE
+              FROM ir_model_data d
+             USING xids x
+             WHERE d.module = x.module
+               AND d.name = x.name
+        """
+        cr.execute(query.format(select_xids))
+
     return deleted