* gnu/java/nio/FileLockImpl.java
	(finalize): Made protected.
	* java/nio/channels/FileChannel.java
	(MapMode.READ_ONLY): Made final.
	(MapMode.READ_WRITE): Made final.
	(MapMode.PRIVATE): Made final.
	* java/nio/channels/SocketChannel.java
	(open): Simplified code.
	* java/nio/channels/spi/AbstractSelectableChannel.java
	(registered): Unused, removed.
	(keyFor): Check channel is open, only locate key
	and not add a new one.
	(register): Don't delete attachments.

From-SVN: r78519