- fix NLSStringHover.internalGetHoverInfo() logic to determine super
  class name of String field so it is fully qualified

Change-Id: I83e5bc17919e613c04890d1caf6d2f4035bd78b0
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.ui/+/192549
Tested-by: JDT Bot <jdt-bot@eclipse.org>
Tested-by: Jeff Johnston <jjohnstn@redhat.com>
Reviewed-by: Jeff Johnston <jjohnstn@redhat.com>