Placeholder & error callback for SvgUri, SvgFromUri and SvgWithCssUri

[AurangShah]

I have used SvgUri, SvgFromUri and SvgWithCssUri for loading the SVG from URI.

I just want to know if this library has the feature to load another placeholder image if the URI is not found or is loading a webpage instead of SVG.

It doesn't have the error callback as well.

Please let me know, It's an essential feature I think.

[WoLewicki]

I think the thing you need has been added in #1503 (see #1503 (comment) how to use it to try and load another svg). There is also #1718 adding same behavior to SvgCssUri. Could you check if it is what you need?

[WoLewicki]

Closing since #2071 has been merged and it provides better handling of parsing error.