Thanks for writing a test!

There's a PlayerTest.makePlayer() function that could make this simpler. https://github.com/videojs/video.js/blob/master/test/unit/test-helpers.js#L8

createEvent is apparently deprecated. 
https://developer.mozilla.org/en-US/docs/Web/API/document.createEvent
Also not supported in ie8, but I guess that's not really an issue in the HTML5 tests. Probably better to use a constructor like MDN says.

It seems like at the core of this you're just testing that preventDefault works, does that sound right?