[OpenJDK 2D-Dev] RFR: 8024343: Change different color with the "The XOR alternation color" combobox, the color of the image can not shown immediately.

[Vadim Pakhnushev]

Hi,
Please review a fix for this bug:
https://bugs.openjdk.java.net/browse/JDK-8024343
It's confidential, so here is a simple explanation:
While rendering with XOR mode set, XRSurfaceData validation method 
doesn't detect subsequent changes in foreground (or xor) color if the 
Composite itself is not changed.
Proposed fix is to validate pixel value independently.
http://cr.openjdk.java.net/~vadim/8024343/webrev.00/
While creating a regression test, I've found that D3D pipeline doesn't 
pass this test, that is drawing in XOR mode into VolatileImage, while 
passing the original test which is drawing to the screen.
So I'm planning to file a new bug for that.

Thanks,
Vadim