hg: jdk/sandbox: 8223810: HotSpot compile warnings from VS2017

[chris.hegarty at oracle.com]

Changeset: f67269c129f9
Author:    dholmes
Date:      2019-05-14 20:29 -0400
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/f67269c129f9

8223810: HotSpot compile warnings from VS2017
Reviewed-by: dholmes, stuefe
Contributed-by: Andrew Luo <andrewluotechnologies at outlook.com>

! src/hotspot/os/windows/os_windows.cpp
! src/hotspot/share/services/attachListener.hpp
! test/hotspot/gtest/gtestMain.cpp