Inventory exposes reference to non-Sync data to an arbitrary thread

Affected versions do not enforce a Sync bound on the type of caller-provided value held in the plugin registry. References to these values are made accessible to arbitrary threads other than the one that constructed them.

A caller could use this flaw to submit thread-unsafe data into inventory, then access it as a reference simultaneously from multiple threads.

The flaw was corrected by enforcing that data submitted by the caller into inventory is Sync.