phpStorm升级后，会检查一些异常，这种应该怎么解决 [ 2.0 版本 ]

phpStorm近期升级后，新增了些新的功能，导致打开项目后，有些会有异常提示甚至报错：
情况一：
Unhandled \yii\web\NotFoundHttpException less... (Ctrl+F1 Alt+T) The inspection reports exceptions which are neither enclosed in a try-catch block nor documented using the '@throws' tag
如图：

看官网上更新说明是这样的：

这种写法有问题吗？
我是自己重写了findModel方法：

/**
     * Finds the OrderMain model based on its primary key value.
     * If the model is not found, a 404 HTTP exception will be thrown.
     * @param integer $id
     * @return OrderMain the loaded model
     * @throws NotFoundHttpException if the model cannot be found
     */
    protected function findModel($id)
    {
        if (($model = OrderMain::findOne($id)) !== null) {
            return $model;
        } else {
            throw new NotFoundHttpException('The requested page does not exist.');
        }
    }

情况二：
Arbitrary expressions in empty are allowed in PHP 5.5 only less... (Ctrl+F1 Alt+T) Checks that language features used in the source code correspond the selected language level. (i.e. traits can be used only in PHP 5.4)

情况三：

这种形式我一直在用，而且现在也不会报错，只是在编辑器的时候就会报错