code: private void populateSecMechList(CSSCompoundSecMechListConfig mechListConfig, List<LayersData> layersList) throws Exception {
          for (LayersData mech : layersList) {
              for (CSSCompoundSecMechConfig cssCompoundSecMechConfig : extractCompoundSecMech(mech)) {
                  mechListConfig.add(cssCompoundSecMechConfig);
              }
          }
      }
docs: /*
  Iterate through each of the "layers" elements to add compound sec mechs to the compound sec mech list.