RFR: JDK-8044343 - Check jdk/src/windows/native/java/lang/ProcessEnvironment_md.c for JNI pending exceptions

Hi, please oblige and review the following change http://cr.openjdk.java.net/~msheppar/8044343/webrev/ which addresses issue https://bugs.openjdk.java.net/browse/JDK-8044343 which is a backport of https://bugs.openjdk.java.net/browse/JDK-8036603 the original changeset didn't apply cleanly and was applied manually http://hg.openjdk.java.net/jdk9/dev/jdk/rev/323b64a9dede regression tests ran ok and finally please approve backport to jdk8u-dev regards Mark