Inferno: New event propagation system

[Havunen]

Implement new event propagation system to support shadow roots and iframes. The basic idea is simple:

• event.composedPath() returns html nodes across The shadow root boundaries. Get the first html node from the stack & loop through them

Implement new benchmark or check If existing event benchmark can be used to make sure there is no regression in performance.

Verify composedPath works through iFrame's

It should fix these:
https://github.com/infernojs/inferno/issues/1439
https://github.com/infernojs/inferno/issues/1430

[Havunen]

We should also measure is it faster to loop dom nodes from composedPath compared to parentNode

[Havunen]

Browser support is horrible for path and composed path...

Neither IE11 nor Edge (v18) supports either path or composedPath. Firefox supports composedPath. Chrome supports both path (it was Google's original idea) and composedPath.

[Havunen]

Closing. Found another way.