I have set debugging to "Developer" mode, and below is the result.
Debug info: SELECT * FROM {context} WHERE id = ? [array ( 0 => '157', )] Error code: invalidrecord
Stack trace:
- line 1365 of /lib/dml/moodle_database.php: dml_missing_record_exception thrown
- line 1341 of /lib/dml/moodle_database.php: call to moodle_database->get_record_select()
- line 5388 of /lib/accesslib.php: call to moodle_database->get_record()
- line 507 of /repository/lib.php: call to context::instance_by_id()
- line 50 of /repository/filesystem/lib.php: call to repository->__construct()
- line 994 of /repository/lib.php: call to repository_filesystem->__construct()
- line ? of unknownfile: call to repository::get_instances()
- line 1107 of /repository/lib.php: call to call_user_func_array()
- line 312 of /admin/repository.php: call to repository::static_function()