[12] RFR: JDK-8210219: GlassClipboard.cpp fails to compile with newer versions of VS2017

[Kevin Rushforth]

Please review the following:

https://bugs.openjdk.java.net/browse/JDK-8210219
https://github.com/javafxports/openjdk-jfx/pull/185

The review is happening on GitHub.

This bug is causing the GitHub AppVeyor builds to fail, since they 
upgraded to a newer version yesterday, but will affect anyone who 
installs a recent Visual Studio compiler. Details are in JBS and the 
GitHub PR.

-- Kevin