[9-dev] GraphicsEnvironment.getHeadlessProperty() does not work for AIX platform

[Jonathan Lu]

Hello,

Could you please review following fix:

Webrev: http://cr.openjdk.java.net/~luchsh/JDK-8058930/
Bug: https://bugs.openjdk.java.net/browse/JDK-8058930

It is a simple fix to make GraphicsEnvironment.getHeadleassProperty() to
return the correct value on AIX.

Many thanks
- Jonathan