RFR: JDK-8036603 - Check jdk/src/windows/native/java/lang/ProcessEnvironment_md.c for JNI pending exceptions

[Mark Sheppard]

Hi,
    Please oblige and review the changes
http://cr.openjdk.java.net/~msheppar/8036603/webrev/

which address the issues raised in
https://bugs.openjdk.java.net/browse/JDK-8036603

summary
JNU_ClassString extracted as parameter to GetMethodID and NewObject calls
and NUL_CHECKed

regards
Mark