8u20 review request: RT-37475 shadow in Ensemble8 Puzzle Pieces demo gets erased

[Jim Graham]

webrev: http://cr.openjdk.java.net/~flar/RT-37475/webrev.00/
Jira: https://javafx-jira.kenai.com/browse/RT-37475
Lengthy explanation of an "aha" moment in the Jira, but the actual fix 
is fairly simple...

                        ...jim