14.4: pageX and pageY coords are not passed to MouseEvent from pointer() call

[sf-kialo]

Reproduction example

https://codesandbox.io/s/heuristic-lake-3rk90q?file=/src/App.js

Prerequisites

1. Set up any page that listens to MouseEvent and log the pageX and pageY properties of the event (as specified in the docs)
2. Simulate a user.pointer event with additional pageX and pageY coords passed like await user.pointer({target: anyTarget, coords: { pageX: 100, pageY: 100 }})
3. Expect the logs to contain the previously defined values for pageX and pageY.

Expected behavior

The properties are properly passed to the mouse event and get logged correctly.

Works correctly in 14.3.

Actual behavior

The value of these properties is undefined.

Broken as of 14.4.0.

User-event version

14.4.3

Environment

See sandbox

Additional context

When the assignProps was changed in this commit, those two properties were omitted.

[liamcmitchell-sc]

Note that from JSDOM@22 pageX/Y/offsetX/Y will alias to clientX/Y until layout support is added:
https://github.com/jsdom/jsdom/blob/a39e0ec4ce9a8806692d986a7ed0cd565ec7498a/lib/jsdom/living/events/MouseEvent-impl.js#L16-L31

You can do this yourself as a workaround:

Object.defineProperties(MouseEvent.prototype, {
  pageX: {
    get() {
      return this.clientX
    },
  },
  pageY: {
    get() {
      return this.clientY
    },
  }
})

Then use x and y in pointer actions:

await user.pointer({
  coords: { x: 100, y: 100 }
})

Using x/y instead of clientX/clientY because of #1139

[su-kialo]

This is still broken as of 14.5.1.

In fact, it's even more broken as the default state is now undefined instead of 0 due to the changes made in the following commit, where pageX and pageY are no longer being initialised:

2852509#diff-3efbb708c7e683da7e8bed053d5b386baa2bf8489e799d1a931db3c4299910c2L43