hg: openjfx/8/graphics/rt: Fix RT-33462: SubScene will NPE for invalid negative width or height. Review by Kevin.

[hang.vo at oracle.com]

Changeset: 8e93e33663b7
Author:    Thor johannesson <thor.johannesson at oracle.com>
Date:      2013-10-18 11:18 -0700
URL:       http://hg.openjdk.java.net/openjfx/8/graphics/rt/rev/8e93e33663b7

Fix RT-33462: SubScene will NPE for invalid negative width or height. Review by Kevin.

! modules/graphics/src/main/java/com/sun/javafx/sg/prism/NGSubScene.java