ZkStateReader.PropsWatcher synchronizes on a string value & doesn't track zk version

While contemplating adding better caching to collection properties to avoid repeated calls to ZK from code that wishes to consult collection properties, I noticed that the existing PropsWatcher class is synchronizing on a string value for the name of a collection. Synchronizing on strings is bad practice, given that you never know if the string might have been interned, and therefore someone else might also synchronizing on the same object without your knowledge creating contention or even deadlocks. Also this code doesn't seem to be doing anything to check ZK version information, so it seems possible that out of order processing by threads could wind up caching out of date data.