Shenandoah changed their barriers to no longer break the to-space invariant, and to no longer need barriers on primitives.

As a result, the "SUPPORT" macros in barrierSetConfig.hpp (SUPPORT_BARRIER_ON_PRIMITIVES and SUPPORT_NOT_TO_SPACE_INVARIANT) are never set. So the conditionalization on them can be removed.

A a result, INTERNAL_BT_BARRIER_ON_PRIMITIVES can always be assumed clear and INTERNAL_BT_TO_SPACE_INVARIANT can always be assumed set. So the (small number) of places examining them can be hard-coded and those decorators can be removed.

The Access::resolve function should also no longer be needed; callers can be cleaned up and it can be removed.