[css-paint-api] Expose DOMMatrix etc

[jakearchibald]

https://drafts.fxtf.org/geometry/ - these functions and classes are useful when working with points in 2d drawing. It feels like they should be available in a paint worklet.

[tabatkins]

Agree, but shouldn't this then be a bug against the Geometry spec to add the right [Exposed] annotations?

[jakearchibald]

Yeah, probably. I couldn't decide, since the paint worklet spec exposes devicePixelRatio itself.