RFR: 8159690: [TESTBUG] Mark headful tests with @key headful.

[Hohensee, Paul]

Please review this backport, which is part of the patch tail for https://icedtea.classpath.org/bugzilla/show_bug.cgi?id=3077.

This is a replacement patch for the one for which a review was requested in https://mail.openjdk.java.net/pipermail/jdk8u-dev/2020-November/012922.html.

JBS issue: https://bugs.openjdk.java.net/browse/JDK-8159690
Original patch: http://hg.openjdk.java.net/jdk9/jdk9/jdk/rev/980da45565c8
3077 patch: http://icedtea.classpath.org//hg/icedtea8-forest/jdk?cmd=changeset;node=dcd850780adc<http://icedtea.classpath.org/hg/icedtea8-forest/jdk?cmd=changeset;node=dcd850780adc>
Webrev: http://cr.openjdk.java.net/~phh/8159690/webrev.8u.jdk.00/

As noted in a comment on the JBS issue, there are 45 tests that were in the original patch that are not in the 3077 patch because they are not present in 8u. Three more are also not in 8u but are in the 3077 patch. Other than those 3, the webrev patch is identical to the 3077 patch.

The patch is not clean with respect to both the original and 3077 patches because the 48 tests are omitted, and because of various context and copyright date differences. The only substantive change is the addition of @headful, which doesn’t affect running any of the tests.

Thanks,
Paul