RFR: 8041602 - (prefs) Check jdk/src/windows/native/java/util/WindowsPreference.c for JNI pending exceptions

Hi, please oblige and review the following change http://cr.openjdk.java.net/~msheppar/8041602/webrev/ which addresses the issue https://bugs.openjdk.java.net/browse/JDK-8041602 which is a backport of https://bugs.openjdk.java.net/browse/JDK-8035340 the original changeset didn't apply cleanly and was applied manually http://hg.openjdk.java.net/jdk9/dev/jdk/rev/740ffd98e35a regression tests ran ok and finally please approve backport to jdk8u-dev regards Mark