RFR: 8041609 - Check jdk/src/windows/native/java/io/WinNTFileSystem_md.c for JNI pending exceptions

[Mark Sheppard]

Hi
     please oblige review and approve the backport to jdk8u-dev, after 
the review of the following change

http://cr.openjdk.java.net/~msheppar/8041609/webrev/

for the issue
https://bugs.openjdk.java.net/browse/JDK-8041609

which is a backport of
https://bugs.openjdk.java.net/browse/JDK-8035870

the hg import  of changeset
http://hg.openjdk.java.net/jdk9/dev/jdk/rev/56366827ebab
didn't apply cleanly so was manually

the regression test run was fine

regards
Mark