RFR: 8248059: [macos] EmptyFolderPackageTest.java failed "hdiutil: create failed - No child processes"

[alexander.matveev at oracle.com]

Please review the jpackage fix for bug [1] at [2].

Added fallback for creating DMG if original approach fails. In original 
approach DMG will be created by providing app image to hdiutil. It was 
noticed that helper sub-processes run by hdiutil to copy app image 
sometimes crashed or failed during automated testing. Fallback approach 
will create empty DMG and copy files manually. It was observed that in 
this case hdiutil does not run sub-process that caused tests to fail, so 
hopefully this workaround will fix issue. Both cases produces same 
working DMG. Tests which failed due to this issue was removed from 
ProblemList.

[1] https://bugs.openjdk.java.net/browse/JDK-8248059
[2] http://cr.openjdk.java.net/~almatvee/8248059/webrev.00/

Thanks,
Alexander