How to use the scratch-svg-renderer.inlineSvgFonts function in scratch-svg-renderer

return function (asset) {

        if (cachedAssetId === asset.assetId) {
            return cachedUrl;
        }

        cachedAssetId = asset.assetId;

        // If the SVG refers to fonts, they must be inlined in order to display correctly in the img tag.
        // Avoid parsing the SVG when possible, since it's expensive.
        if (asset.assetType === storage.AssetType.ImageVector) {
            const svgString = asset.decodeText();
            if (svgString.match(HAS_FONT_REGEXP)) {
                const svgText = inlineSvgFonts(svgString);
                cachedUrl = `data:image/svg+xml;utf8,${encodeURIComponent(svgText)}`;
            } else {
                cachedUrl = asset.encodeDataURI();
            }
        } else {
            cachedUrl = asset.encodeDataURI();
        }

        return cachedUrl;
    };
}());

// Export svg
    const guideLayers = hideGuideLayers(true /* includeRaster */);
    const bounds = paper.project.activeLayer.drawnBounds;
    const svg = paper.project.exportSVG({
        bounds: 'content',
        matrix: new paper.Matrix().translate(-bounds.x, -bounds.y)
    });
    showGuideLayers(guideLayers);

    // Get rid of anti-aliasing
    // @todo get crisp text https://github.com/LLK/scratch-paint/issues/508
    svg.setAttribute('shape-rendering', 'crispEdges');

    let svgString = (new XMLSerializer()).serializeToString(svg);
    svgString = inlineSvgFonts(svgString);

    // Put anti-aliased SVG into image, and dump image back into canvas
    const img = new Image();
    img.onload = () => {
        if (img.width && img.height) {
            getRaster().drawImage(
                img,
                new paper.Point(Math.floor(bounds.topLeft.x), Math.floor(bounds.topLeft.y)));
        }
        paper.project.activeLayer.removeChildren();
        onUpdateImage(false /* skipSnapshot */, Formats.BITMAP /* formatOverride */);
    };
    img.onerror = () => {
        // Fallback if browser does not support SVG data URIs in images.
        // The problem with rasterize is that it will anti-alias.
        const raster = paper.project.activeLayer.rasterize(72, false /* insert */);