[devtools] CubicWebTC._check_html may have to deal with unicode or bytes If called with template=None, CubicWebTC.view will not go through main-template, and return the unicode data from the view directly instead of encoded data.

drop_relation_definition('CWSourceSchemaConfig', 'cw_schema', 'CWAttribute')
sync_schema_props_perms('cw_schema')