src/ExtensionAPI.js
function ExtensionAPI(chartInstance) {
    zrUtil.each(echartsAPIList, function (name) {
        this[name] = zrUtil.bind(chartInstance[name], chartInstance);
    }, this);
}
function ExtensionAPI(chartInstance) {
    zrUtil.each(echartsAPIList, function (name) {
        this[name] = zrUtil.bind(chartInstance[name], chartInstance);
    }, this);
}
function ExtensionAPI ( chartInstance ) { zrUtil . each ( echartsAPIList , function ( name ) { this [ name ] = zrUtil . bind ( chartInstance [ name ] , chartInstance ) ; } , this ) ; }
And `getCoordinateSystems` and `getComponentByElement` will be injected in echarts.js
And getCoordinateSystems and getComponentByElement will be injected in echarts . js