code: public Resource getFavIcon(String siteRoot) {
  
          CmsResource iconResource = null;
          try {
              iconResource = getRootCmsObject().readResource(siteRoot + "/" + CmsSiteManager.FAVICON);
          } catch (CmsException e) {
              //no favicon there
          }
          if (iconResource != null) {
              return new ExternalResource(
                  OpenCms.getLinkManager().getPermalink(getRootCmsObject(), iconResource.getRootPath()));
          }
          return new CmsCssIcon(OpenCmsTheme.ICON_SITE);
      }
docs: Returns the fav icon path for the given site.<p>
  
  @param siteRoot the site root
  
  @return the icon path