hg: openjfx/10-dev/rt: 8191621: Windows build fails if VS150COMNTOOLS is set

[murali.billa at oracle.com]

Changeset: c91ffeb5bb67
Author:    mbilla
Date:      2017-11-30 18:38 +0530
URL:       http://hg.openjdk.java.net/openjfx/10-dev/rt/rev/c91ffeb5bb67

8191621: Windows build fails if VS150COMNTOOLS is set
Reviewed-by: kcr

! buildSrc/genVSproperties.bat