When doing an in-tree build, Makefile.gen.sh isn't ignoring any .java files
generated from .javain files (it can see both), instead adding both to
GEN_SOURCES. Makes for a very confused automake error.
2005-11-21 Andrew Cagney <firstname.lastname@example.org>
* Makefile.rules (.java.classes): Delete rule.
* Makefile.gen.sh: Do not generate .classes.o dependency. Do not
add a .java file to GEN_SOURCES when there is a .javain.