Gtk: fx applet can not show in full screen mode on linux

Issue found on ubuntu 10 with JRE7u6 b15
Open below URL in safari 5.1+:
http://sqeweb.us.oracle.com/deployment1/deployment_6_UR_int_exec_ws/6/deployment/src/javafx/fxfeaturesTest/fxfeaturesTest/html/FullscreenTest.html
Click on "toggle fullscreen" button with browser. If you can not see full screen occupied and the applet area is looking strange, the issue is reproduced.