use native ResizeObserver when available

[indirectlylit]

Hi there - great library, thank you!

Heads-up that there might be a ResizeObserver coming in spec eventually. Would be great if the library would use the native implementation when available.

See:

• https://developers.google.com/web/updates/2016/10/resizeobserver
• https://wicg.github.io/ResizeObserver/
• Polyfill WICG/resize-observer#3

thanks!

[marcj]

Yeah, but I guess it will take ages until we have it available.

[indirectlylit]

true, looks like it'll just be chrome for a while