Implement the Encrypted Media Extensions as defined at http://dvcs.w3.org/hg/html-media/raw-file/tip/encrypted-media/encrypted-media.html.
This is an umbrella bug for the overall feature. Individual patches will be dependencies.
Please send an e-mail to webkit-dev announcing this feature. We need to give everyone a chance to discuss whether this is something we needs, as well as implementation strategy.
For some definition of implemented, this has been done. This particular bug arc is now out of date, being based on old versions of the spec.