Version 1.16 is long ago and there seems no need to keep the const ParserCache::try116cache in core.
const try116cache = false; /* Only useful $wgParserCacheExpireTime after updating to 1.17 */
Maybe ParserOptions::legacyOptions can be deprecated/removed in that way, because it looks only used in this case.
Version: 1.23.0
Severity: normal