Merge pull request #15762 (Chromium update)

This is the original pull request plus some commits from me to bring all
channels to the latest versions, because the fixed security
vulnerabilites might not be fixed in the dev version we had before.

I've tested the whole changeset on my Hydra at:

https://headcounter.org/hydra/eval/322006

Thanks to @srp for the initial commit and thus implicitly also for the
security notice.

Cc: @abbradar