DrmInfo callbacks fail to compare if they are closures or bound

[joeyparrish]

If your app's ContentProtection callback returns multiple DrmInfos with callbacks which are either closures or bound separately on each callback invocation, these callbacks don't compare as equal to each other.

This bug affects v1.5.0 and v1.5.1.

[joeyparrish]

Fixed in 6263e1f.