[css-font-load-events] More definitionbikeshed

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extra : rebase_source : 00f6038a958e22af77b56d944b0b94fe7bc14156
[css-font-load-events] More work! Starting on events now.

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extra : rebase_source : d31cf2b99e0e96c1f778d870a5a401ee244dc96d