[9] Review request: JDK-8088857 Menu slow to respond after resizing a window multiple times with animation running

[Jim Graham]

JBS: https://bugs.openjdk.java.net/browse/JDK-8088857
webrev: http://cr.openjdk.java.net/~flar/JDK-8088857/webrev.rt.00/

Fix is as we discussed.

I'll investigate applying it to 8u-dev soon...

                        ...jim