Disallow asymmetric visibility on static properties

This check was forgotten in the original implementation. Relaxing this
restriction shouldn't be hard, but needs some work. We either n

Disallow asymmetric visibility on static properties

This check was forgotten in the original implementation. Relaxing this
restriction shouldn't be hard, but needs some work. We either need to prevent
merging of cache slots for R/RW/W, or we need to introduce an additional check
when writing to the property indirectly. This check is currently present only
for direct writes.

Closes GH-16462

show more ...