code: public JSModule getDeepestCommonDependencyInclusive(
        Collection<JSModule> modules) {
      Iterator<JSModule> iter = modules.iterator();
      JSModule dep = iter.next();
      while (iter.hasNext()) {
        dep = getDeepestCommonDependencyInclusive(dep, iter.next());
      }
      return dep;
    }
docs: Returns the deepest common dependency of the given modules.