(feature) EventTarget API on host elements

[necolas]

Describe the feature request

The EventTarget interface is implemented by objects that can receive events and may have listeners for them. Native does not currently support this API on host elements.

Previously we had introduced a prototype implementation of addEventListener and removeEventListener in React Native, but it was removed as it needs to be reimplemented properly and integrated with broader changes to React Native. For example, the events need to conform to W3C standards in terms of timing and event payload.

In the meantime, we may be able to polyfill this API using event emitters and the new traversal APIs, which would allow us to emulate capture/bubble phases of events. But, ideally we'd build this into React Native given it would be more performant and there is already an existing event system.