servo: Merge #14533 - Alphabetize document.createEvent match list (from frewsxcv:events); r=Ms2ger

Makes it easier to see what hasn't been implemented with regards to the
spec.

Source-Repo: https://github.com/servo/servo
Source-Revision: 120b003195383041b9f182fc03103e50f9249e49

UltraBlame original commit: fc94a472712b69aea05a8a164c0078949b848687

Author: marco-c