[8] Request for review: JDK-8015589 Test java/awt/Window/Grab/GrabTest.java fails on MacOSX

[Anton V. Tarasov]

Hello,

Please, review the fix:
jira: https://jbs.oracle.com/bugs/browse/JDK-8015589
webrev: http://cr.openjdk.java.net/~ant/JDK-8015589/webrev.0

The test failed because mouse click didn't happen outside the frame on 
Mac as it was expected.
I indented a little further.

Thanks,
Anton.