code: private Set<String> getSchemaHeadIncludes(CmsObject cms, CmsResource res, String type) throws CmsLoaderException {
  
          if (type.equals(TYPE_CSS)) {
              return getCSSHeadIncludes(cms, res);
          } else if (type.equals(TYPE_JAVASCRIPT)) {
              return getJSHeadIncludes(cms, res);
          }
          return null;
      }
docs: Gets the head includes of a resource from the content definition.<p>
  
  @param cms the current CMS context
  @param res the resource for which the head includes should be fetched
  @param type the head include type (CSS or Javascript)
  
  @return the set of schema head includes
  
  @throws CmsLoaderException if something goes wrong