cacheAttribute(attr, value) {
    var component;
    var componentName;

    // Get component data.
    componentName = _utils_index_js__WEBPACK_IMPORTED_MODULE_2__.split(attr, MULTIPLE_COMPONENT_DELIMITER)[0];
    component = _component_js__WEBPACK_IMPORTED_MODULE_1__.components[componentName];
    if (value === undefined) {
      value = window.HTMLElement.prototype.getAttribute.call(this, attr);
    }
    this.rawAttributeCache[attr] = value;
    if (!component) {
      return;
    }
    this.componentCache[attr] = this.parseComponentAttrValue(component, value);
  }
If `attr` is a component, then parse the value using the schema and store it.