- Fix for varargs to propagate to supertype method
- Add tests

Change-Id: I1dd6d7e3273db20758d08825864fddd3f39f6344
Signed-off-by: Kenneth Styrberg <kenneth@kean.nu>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.ui/+/189566
Tested-by: Jeff Johnston <jjohnstn@redhat.com>
Tested-by: JDT Bot <jdt-bot@eclipse.org>
Reviewed-by: Jeff Johnston <jjohnstn@redhat.com>