code: static String getResourceSubTypeIconClass(String resourceTypeName, String suffix, boolean small) {
  
          StringBuffer buffer = new StringBuffer(CmsGwtConstants.TYPE_ICON_CLASS).append("_").append(
              resourceTypeName.hashCode()).append("_").append(suffix);
          if (small) {
              buffer.append(SMALL_SUFFIX);
          }
          return buffer.toString();
      }
docs: Returns the CSS class for a given resource type name and file name extension.<p>
  
  @param resourceTypeName the resource type name
  @param suffix the file name extension
  @param small if true, get the icon class for the small icon, else for the biggest one available
  
  @return the CSS class for the type and extension