Fixes maranran#20 via fork from BasitAli

Author: marcus-herrmann

lib/utils/index.js

@@ -55,7 +55,7 @@ module.exports = {
     return (ariaLabelProp && this.hasAttributeValue(ariaLabelProp)) || (arialLabelledByProp && this.hasAttributeValue(arialLabelledByProp));
   },
   getAttribute (node, attr) {
-    return utils.getAttribute(node, attr) || this.getDirective(node, 'bind', attr);  // todo eslint-plugin-vue util.getDirective 稳定后换回
+    return utils.getAttribute(node, attr) || utils.getDirective(node, 'bind', attr);
   },
   getDirective (node, name, argument) {
     assert(node && node.type === 'VElement')