convert-svg-polygon-to-path
HTML
<svg class="elephant">
<g transform="scale(1.5)">
<polygon fill="#000000" points=" 8.763,26.584 0.598,56.484 9.003,76.657 11.764,75.815 11.404,74.615 4.68,56.724 13.686,49.999 14.886,47.598 14.886,51.44 20.53,47.358 23.412,49.579 30.211,82.301 37.537,82.301 41.423,58.404 68.438,62.968 74.084,63.089 81.289,82.301 91.974,82.301 87.892,61.647 94.977,40.513 97.761,57.646 97.321,60.208 98.274,65.746 99.402,59.967 98.24,57.566 96.297,39.313 81.169,23.342 33.4,23.305 32.36,24.025 30.497,22.262"></polygon>
</g>
</svg>
JavaScript
var polys = document.querySelectorAll('polygon,polyline');
[].forEach.call(polys,convertPolyToPath);
function convertPolyToPath(poly){
var svgNS = poly.ownerSVGElement.namespaceURI;
var path = document.createElementNS(svgNS,'path');
var points = poly.getAttribute('points').split(/\s+|,/);
var x0=points.shift(), y0=points.shift();
var pathdata = 'M'+x0+','+y0+'L'+points.join(' ');
if (poly.tagName=='polygon') pathdata+='z';
path.setAttribute('id',poly.getAttribute('id'));
path.setAttribute('fill',poly.getAttribute('fill'));
path.setAttribute('stroke',poly.getAttribute('stroke'));
path.setAttribute('d',pathdata);
poly.parentNode.replaceChild(path,poly);
}