Use fixupSVGString from scratch-svg-renderer

src/containers/paper-canvas.jsx

@@ -3,6 +3,7 @@ import PropTypes from 'prop-types';
 import React from 'react';
 import {connect} from 'react-redux';
 import paper from '@scratch/paper';
+import {fixupSvgString} from 'scratch-svg-renderer';
 import Formats from '../lib/format';
 import log from '../log/log';
 
@@ -194,15 +195,7 @@ class PaperCanvas extends React.Component {
     importSvg (svg, rotationCenterX, rotationCenterY) {
         const paperCanvas = this;
         // Pre-process SVG to prevent parsing errors (discussion from #213)
-        // 1. Remove svg: namespace on elements.
-        svg = svg.split(/<\s*svg:/).join('<');
-        svg = svg.split(/<\/\s*svg:/).join('</');
-        // 2. Add root svg namespace if it does not exist.
-        const svgAttrs = svg.match(/<svg [^>]*>/);
-        if (svgAttrs && svgAttrs[0].indexOf('xmlns=') === -1) {
-            svg = svg.replace(
-                '<svg ', '<svg xmlns="http://www.w3.org/2000/svg" ');
-        }
+        svg = fixupSvgString(svg);
 
         // Get the origin which the viewBox is defined relative to. During import, Paper will translate
         // the viewBox to start at (0, 0), and we need to translate it back for some costumes to render