8037177: -Dnashorn.optimistic should be enabled by default, meaning that it has to be explicitly set to false to run with the jdk 8 style conservative types Summary: This will be the new default setting, so the explicit flag should be removed, and instead reverse checked for explicitly DISABLED optimistic types. In the future, we might remove the flag altogether. Reviewed-by: attila, hannesw

8036127: Prototype filter needs to be applied to getter guard as well, not just getter Summary: This manifests itself as a bug in optimistic types, as inner functions may access properties of the wrong type, but it is also a bug in tip. Without optimistic types, we have been unable to find a reproducer due to more similar PropertyMaps Reviewed-by: attila, jlaskey, sundar