Range TS

[maryia-lapata]

Summary

This PR updates TS def for onChange method of EuiRange.

[elasticmachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[maryia-lapata]

In case if we don't omit onChange def from InputHTMLAttributes<HTMLInputElement>, EuiRange's onChange requires ((event: React.ChangeEvent<HTMLInputElement>) => void) & ((event: React.ChangeEvent<HTMLInputElement> | React.MouseEvent<HTMLButtonElement, MouseEvent>, isValid: boolean) => void)) def.

[maryia-lapata]

@chandlerprall getting back to the comment #2211 (comment), React.MouseEvent<HTMLButtonElement> limits target and if we want to use target's valueAsNumber the event should be cast to React.ChangeEvent<HTMLInputElement> (e.g. https://github.com/elastic/kibana/pull/45902/files#diff-e08b038e0994227720936e08475c5502R57). Maybe you have some idea how to avoid casting?

[chandlerprall]

Changes LGTM, created an empty typescript project locally, added EUI as a dependency, and verified the bug before this change and that it is fixed with this it.

Needs a bugfix entry to CHANGELOG.md before merging

[chandlerprall]

jenkins test this

[chandlerprall]

You can access valueAsNumber (TIL about this attribute!) without casting by type checking first -

if (e.currentTarget instanceof HTMLInputElement) {
    ... do something with e.currentTarget.valueAsNumber ...
}

[chandlerprall]

Changes LGTM! Tested locally by consuming change in an new TS project