Replaced getUINameFromCommand by GetMenuLabelForCommand

Change-Id: Icd89fed4d9944653996a2218c6ed80af72cefe89
Reviewed-on: https://gerrit.libreoffice.org/21464Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>
Tested-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>