message: fix(svg): fix shadow error on Text.
diff: @@ -232,10 +232,11 @@ SVGPainter.prototype = {
  prevSvgElement = textSvgElement || svgElement
  || prevSvgElement;
  + // zrender.Text only create textSvgElement.
  this.gradientManager
  - .addWithoutUpdate(svgElement, displayable);
  + .addWithoutUpdate(svgElement || textSvgElement, displayable);
  this.shadowManager
  - .addWithoutUpdate(svgElement, displayable);
  + .addWithoutUpdate(svgElement || textSvgElement, displayable);
  this.clipPathManager.markUsed(displayable);
  }
  }
  @@ -244,15 +245,17 @@ SVGPainter.prototype = {
  var displayable = newVisibleList[item.indices[k]];
  prevSvgElement = getTextSvgElement(displayable)
  || getSvgElement(displayable) || prevSvgElement;
  - svgElement = getSvgElement(displayable) || getTextSvgElement(displayable);
  +
  + var svgElement = getSvgElement(displayable);
  + var textSvgElement = getTextSvgElement(displayable);
  this.gradientManager.markUsed(displayable);
  this.gradientManager
  - .addWithoutUpdate(svgElement, displayable);
  + .addWithoutUpdate(svgElement || textSvgElement, displayable);
  this.shadowManager.markUsed(displayable);
  this.shadowManager
  - .addWithoutUpdate(svgElement, displayable);
  + .addWithoutUpdate(svgElement || textSvgElement, displayable);
  this.clipPathManager.markUsed(displayable);
  }
  