Added BaseRenderingContext2D.prototype.roundRect

[codyebberson]

BaseRenderingContext2D.prototype.roundRect: https://html.spec.whatwg.org/multipage/canvas.html#canvasrenderingcontext2d

Path2D.prototype.roundRect: https://html.spec.whatwg.org/multipage/canvas.html#path2d-objects

Both refer to: https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-roundrect

[codyebberson]

Hi @h-joo - anything I can do to improve this?

[codyebberson]

@niloc132 - thank you for the review

I added the function definition to the CanvasPathMethods as well. Good catch.

This now follows the exact same pattern as rect in CanvasPathMethods, BaseRenderingContext2D, and Path2D.

[codyebberson]

Hi @h-joo and @niloc132 - Anything I can do to move this along?

[niloc132]

Sorry, I'm just a contributor, I don't have any special powers to get patches merged.