Upgrade Gtest due to VS2017 (C4996) std::tr1 namespace and TR1-only machinery deprecation

Compiling gtest with VS2017 yields the following issue:

<directory>open\test\fmw\gtest\include\gtest/gtest-printers.h(497): warning C4996: 'std::tr1': warning STL4002: The non-Standard std::tr1 namespace and TR1-only machinery are deprecated and will be REMOVED. You can define
_SILENCE_TR1_NAMESPACE_DEPRECATION_WARNING to acknowledge that you have received this warning.

This issue has been temporarily worked around by adding DISABLED_WARNINGS_CXX_microsoft := 4996 to make/hotspot/lib/CompileGtest.gmk.

gtest should be upgraded to determine if recent versions have been updated to handle this deprecation.