HDFSFileFinder PROGRAM, but if we don't put in a _SOURCES line at all,
Automake will default to "HDFSFileFinter_class_SOURCES =
HDFSFileFinder.c", which clearly will cause problems.
But we don't want to put the .java file in _SOURCES, either, because
we haven't configured Automake to handle Java (because current
versions of Automake only have GCJ, not other Java compilers). So set
HDFSFileFinder_class_SOURCES to blank and list the .java file in
EXTRA_SOURCES (so that they get picked up for "make dist").
This commit was SVN r26424.
