This is the mirror image of #2170.

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Add `default_converter` argument to `to_js` and `toJs`. This is the mirror image of #2170.

### Checklists

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     just remove those checkboxes, or mark them as checked. Otherwise,
     if some checkboxes are left unmarked, we might assume that your PR
     is not ready to be merged and we might keep you waiting -->

- [x] Add a [CHANGELOG](https://github.com/pyodide/pyodide/blob/main/docs/project/changelog.md) entry
- [x] Add / update tests
- [x] Add new / update outdated documentation

#ifndef KEYBOARD_INTERRUPT_H
#define KEYBOARD_INTERRUPT_H

int
keyboard_interrupt_init();

#endif /* KEYBOARD_INTERRUPT_H */

#ifndef KEYBOARD_INTERRUPT_H
#define KEYBOARD_INTERRUPT_H

int
keyboard_interrupt_init();

#endif /* KEYBOARD_INTERRUPT_H */
