Function extend

_benchmarks/sample_echarts.js:276–288

(target, source)

        return result;
    }
    function extend(target, source) {
        if (Object.assign) {
            Object.assign(target, source);
        }
        else {
            for (var key in source) {
                if (source.hasOwnProperty(key)) {
                    target[key] = source[key];
                }
            }
        }
        return target;
    }
    function defaults(target, source, overlay) {
        var keysArr = keys(source);
        for (var i = 0; i < keysArr.length; i++) {