+ * - known-revision-output: a combined canonical ParserOutput for the revision, perhaps
+ * from some cache. The caller is responsible for ensuring that the ParserOutput indeed
+ * matched the $rev and $options. This mechanism is intended as a temporary stop-gap,
+ * for the time until caches have been changed to store RenderedRevision states instead
+ * of ParserOutput objects. (default: null) (since 1.33)