8036979 added the new setOption() and getOption() methods to the various socket classes in java.net.
Originally, it was intended to implement these methods independent of the underlying SocketImpls.

This turned out to be problematic and the implementation needs to be delegated to the impl (with a default implementation for legacy options).

To support this setOption, getOption and supportedOptions need to be added to SocketImpl.

Also, the existing public supportedOptions() methods need to throw IOException now.