网上普遍解决方法是说es6配置问题，实际没有解决我的问题，修改UglifyJs配置解决，方案如下

旧代码

new webpack.optimize.UglifyJsPlugin({
    mangle: {
        except: ['$super', '$', 'exports', 'require', 'module', '_']
    },
    compress: {
        warnings: false
    },
    output: {
        comments: false,
    },
    sourceMap: config.build.productionSourceMap,
    parallel: true
}),

新代码

new UglifyJsPlugin({
    "uglifyOptions":
        {
            mangle: {
                reserved: ['$super', '$', 'exports', 'require', 'module', '_']
            },
            compress: {
                warnings: false
            },
            output: {
                comments: false,
            },
            sourceMap: config.build.productionSourceMap,
            parallel: true
        }
    }
),