Per recent MSE spec change [1], MSE objects should have EventHandler attributes for their various events. The logic for the events does not change; this feature just adds support for them via EventHandler attributes. [1] https://github.com/w3c/media-source/pull/75
Docs: https://github.com/w3c/media-source/issues/66 https://github.com/w3c/media-source/pull/75