[FIX] default_FIELD from context should not overwrite modified FIELD value while creating record

lp bug: https://launchpad.net/bugs/516964 fixed

bzr revid: jvo@tinyerp.com-20100204121656-pzh1opx6kbrywscg

bin/osv/orm.py

@@ -2140,7 +2140,7 @@ class orm(orm_template):
                     field_value = field_value2
                 value[field] = field_value
         for key in context or {}:
-            if key.startswith('default_'):
+            if key.startswith('default_') and (key[8:] in fields_list):
                 value[key[8:]] = context[key]
         return value