Patch: RFA PR libgcj/15430 (read keeps blocking after socket closed).

[David Daney]

David Daney wrote:

> +static void 
> +throw_on_sock_closed (gnu::java::net::PlainSocketImpl *soc_impl)
> +{
> +    // Avoid races from asynchronous close().
> +    JvSynchronize sync (soc_impl);
> +    if (soc_impl->native_fd == -1) {
> +      // Socket was closed while blocked in recv.

This comment ^^^^^^ is a little misleading/incorrect.  I will fix it if 
approved.

David Daney.