Christoph Büscher aa0c586b73 Deprecate _field_names disabling (#42854)
Currently we allow `_field_names` fields to be disabled explicitely, but since
the overhead is negligible now we decided to keep it turned on by default and
deprecate the `enable` option on the field type. This change adds a deprecation
warning whenever this setting is used, going forward we want to ignore and finally
remove it.

Closes #27239
2019-09-11 14:58:08 +02:00
..