code: public void addRef(String name, TypeMirror elementType, boolean isArray) {
      refs.add(new RefInfo(name, elementType, isArray));
    }
docs: Register a ref found in the template
  @param name The name of the ref
  @param elementType The type of the element the Ref is on
  @param isArray Whether the ref is in a v-for (should be an array)