Run the jni tests using the interpreter.

	Run the jni tests using the interpreter.
	* testsuite/libjava.jni/jni.exp (gcj_jni_compile_c_to_so): Append
	options_cxx to shared lib compile command.
	(gcj_jni_test_one): Pass cxxflags to gcj_jni_compile_c_to_so, so
	they are used to link the shared lib, not the main binary.
	Use libjava_invoke to run gij.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@81574 138bc75d-0d04-0410-961f-82ee72b054a4