message: fix(svg): fix exported svg cannot be opened when using external image.(apache/incubator-echarts#13655)
  error info: namespace prefix xlink for href on use is not defined
diff: @@ -24,7 +24,6 @@ import Storage from '../Storage';
  import { GradientObject } from '../graphic/Gradient';
  import { PainterBase } from '../PainterBase';
  import {PatternObject} from '../graphic/Pattern';
  -import env from '../core/env'
  function parseInt10(val: string) {
  return parseInt(val, 10);
  @@ -117,8 +116,9 @@ class SVGPainter implements PainterBase {
  this._opts = opts = util.extend({}, opts || {});
  const svgDom = createElement('svg');
  - // IE: avoid getting double xmlns attributes when exporting to svg
  - env.browser.ie || svgDom.setAttribute('xmlns', 'http://www.w3.org/2000/svg');
  + svgDom.setAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns', 'http://www.w3.org/2000/svg');
  + svgDom.setAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:xlink', 'http://www.w3.org/1999/xlink');
  +
  svgDom.setAttribute('version', '1.1');
  svgDom.setAttribute('baseProfile', 'full');
  svgDom.style.cssText = 'user-select:none;position:absolute;left:0;top:0;';
  @@ -468,7 +468,7 @@ class SVGPainter implements PainterBase {
  outerHTML
  .replace(/></g, '>\n\r<')
  // PENDING: remove &quot; ?
  - .replace(/&quot;/g, ''));
  + .replace(/url\(&quot;([^)]*)&quot;\)/gm, 'url($1)'));
  return 'data:image/svg+xml;charset=UTF-8,' + html;
  }
  refreshHover = createMethodNotSupport('refreshHover') as PainterBase['refreshHover'];
  