Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  f4d12988ea880854a5e348e242861114bc436b66

Hygiene: remove fallback for no header-loaded event

This was added in September in d5a36e4, it should be safe to remove it now.

Change-Id: I15e4cf43d47ddf8864003556be85496bf27f0e17