[14] RFR: 8236772: Fix build for windows 32-bit after 8212160 and 8234331.

[Lindenmaier, Goetz]

Hi,

Two warning fail the windows 32 bit build with VS 2017.

In count_leading_zeroes.hpp, a declaration is not included
in the _LP64 that covers all it's uses. Thus a warning
about an unused variable is raised.

A library for a test lacks the JNIEXPORT and JNICALL
required to match the signature in jvmti.h.

I'd like to push this to jdk14.

Please review:
http://cr.openjdk.java.net/~goetz/wr20/8236772-fix_ntintel_build-jdk14/01/

Best regards,
  Goetz.