tools: refloat 7 Node.js patches to cpplint.py

Cherry-pick 12c8b4d1
Original commit message:
    This commit is a suggestion for adding a rule for NULL usages in the
    code base. This will currently report a number of errors which could be
    ignored using // NOLINT (readability/null_usage)

    PR-URL: https://github.com/nodejs/node/pull/17373


Reviewed-By: Jon Moss <me@jonathanmoss.me>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Timothy Gu <timothygu99@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>

Refs: https://github.com/nodejs/node/commit/12c8b4d15471cb6211b39c3a2ca5b10fa4b9f12b

Cherry-pick fc81e801
Original commit message:

    Update cpplint.py to check for inline headers when the corresponding
    header is al...