Add test coverage for passing `NULL` to each parameter of
`napi.*(propert|element)` and `napi_set_prototype`. In the case of
`napi_define_properties` also test setting various initializer fields
to `NULL`.

PR-URL: https://github.com/nodejs/node/pull/31488
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

This is a refactoring of https://github.com/nodejs/node/issues/27628
following https://github.com/nodejs/node/pull/28505.

This change factors out functions `add_last_status()` and
`add_returned_status()` so they may be reused in the tests for passing
information about the last error status and/or a returned `napi_status`
to JavaScript.

PR-URL: https://github.com/nodejs/node/pull/28848
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gabriel Schulhof <gabriel.schulhof@intel.com>

Partition test/addons-napi into test/js-native-api and test/node-api to
isolate the Node.js-agnostic portion of the N-API tests from the
Node.js-specific portion.

PR-URL: https://github.com/nodejs/node/pull/24557
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>