hg: jdk/hs: 8198304: VS2017 (C4838, C4312) Various conversion issues with gtest tests

[lois.foltan at oracle.com]

Changeset: ba9da6aaae36
Author:    lfoltan
Date:      2018-02-26 10:11 -0500
URL:       http://hg.openjdk.java.net/jdk/hs/rev/ba9da6aaae36

8198304: VS2017 (C4838, C4312) Various conversion issues with gtest tests
Summary: Introduce specific casts to fix multiple type cast conversion compilation errors.
Reviewed-by: gtriantafill, hseigel

! test/hotspot/gtest/memory/test_guardedMemory.cpp
! test/hotspot/gtest/utilities/test_align.cpp