function dataURLToBlob(dataURL) {
        var type = dataURL.match(/data:([^;]+)/)[1];
        var base64 = dataURL.replace(/^[^,]+,/, '');
        var buff = binaryStringToArrayBuffer(atob(base64));
        return createBlob([buff], { type: type });
    }
Convert a data URL string
(e.g. <code>'data:image/png;base64,iVBORw0KG...'</code>)
to a <code>Blob</code>.

Example:

```js
var blob = blobUtil.dataURLToBlob(dataURL);
```

@param dataURL - dataURL-encoded string
@returns Blob