Add createRadialGradient to ICanvas

[yuripourre]

Description borrowed from: https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/createRadialGradient

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[RaananW]

LGTM, will let @sebavan merge.

[sebavan]

I guess this should only be done if we intent to support it as well on Native otherwise ppl should cast in the web to HTMLElement Canvas.

@bghgary, @CedricGuillemet is it something we can easily add in Native ?

[sebavan]

Blocking the merge until we get some info from the native team.

[CedricGuillemet]

It's partially supported : https://github.com/memononen/nanovg/blob/397f3300bc14bdb856ec429c71c345ab0340b0a6/src/nanovg.h#L414

with native x0,y0 and x1,y1 must be same value.

[sebavan]

It's partially supported : https://github.com/memononen/nanovg/blob/397f3300bc14bdb856ec429c71c345ab0340b0a6/src/nanovg.h#L414

with native x0,y0 and x1,y1 must be same value.

So it does make sense to merge this one ?

[sebavan]

Mainly wondering as it could create discrepancies between the two ?

[CedricGuillemet]

Mainly wondering as it could create discrepancies between the two ?

There are already discrepancies between native and Web. Like drawImage is partially supported and some modes will render nothing or incorrectly. We don't have a lot of traction for Native GUI atm. So, if this PR is mandatory for future dev, merge it.