* java/io/FileDescriptor.java
	(lock): New method.
	(tryLock): New method.
	(unlock): New method.
	* java/io/natFileDescriptorEcos.cc
	(lock): New method.
	(tryLock): New method.
	(unlock): New method.
	* java/io/natFileDescriptorPosix.cc
	(lock): New method.
	(tryLock): New method.
	(unlock): New method.
	* java/io/natFileDescriptorWin32.cc
	(lock): New method.
	(tryLock): New method.
	(unlock): New method.

From-SVN: r76421