* java/net/JarURLConnection.java (getCertificates): New method
	from Classpath.
	* java/net/URLClassLoader.java (URLClassLoader): Extends
	SecureClassLoader.
	(definePackage): New method from Classpath.
	(getPermissions): Likewise.
	(newInstance): Likewise.
	(findClass): Construct CodeSource for new class (from Classpath).
	* java/net/SocketImpl.java (shutdownInput, shutdownOutput): New
	methods.
	* java/net/URL.java (getUserInfo): New method.
	(set(String,String,int,String,String,String,String,String)): New
	method.
	* java/net/PlainSocketImpl.java (_Jv_SO_KEEPALIVE_): Define.
	(shutdownInput, shutdownOutput): Declare.
	* java/net/PlainDatagramSocketImpl.java (_Jv_SO_KEEPALIVE_):
	Define.
	* java/net/natPlainSocketImpl.cc (setOption): Handle keepalive.
	(getOption): Likewise.
	(shutdownInput): New method.
	(shutdownOutput): Likewise.
	* java/net/natPlainDatagramSocketImpl.cc (setOption): Handle
	keepalive.
	(getOption): Likewise.
	* java/net/SocketOptions.java (SO_KEEPALIVE): New constant.
	* java/net/Socket.java (setKeepAlive): New method.
	(getKeepAlive): Likewise.
	(shutdownInput, shutdownOutput): New methods.

From-SVN: r56685